Undocumented Parameters in Oracle 11g

In this post, I will give a list of all undocumented parameters in Oracle 11g. Here is a query to see all the parameters (documented and undocumented) which contain the string you enter when prompted:

– Enter name of the parameter when prompted

SET linesize 235
col Parameter FOR a50
col Instance FOR a55
col S FOR a1
col I FOR a1
col D FOR a1
col Description FOR a90

  a.ksppinm  "Parameter",
  decode(p.isses_modifiable,'FALSE',NULL,NULL,NULL,b.ksppstvl) "Session",
  c.ksppstvl "Instance",
  decode(p.isses_modifiable,'FALSE','F','TRUE','T') "S",
  decode(p.issys_modifiable,'FALSE','F','TRUE','T','IMMEDIATE','I','DEFERRED','D') "I",
  decode(p.isdefault,'FALSE','F','TRUE','T') "D",
  a.ksppdesc "Description"
FROM x$ksppi a, x$ksppcv b, x$ksppsv c, v$parameter p
WHERE a.indx = b.indx AND a.indx = c.indx
  AND p.name(+) = a.ksppinm
  AND UPPER(a.ksppinm) LIKE UPPER('%&1%')
ORDER BY a.ksppinm;

Enter value for 1: 
Here is the list of all undocumented parameters in Oracle 11g  :
Parameter Name Parameter Value Description
_4031_dump_bitvec 67194879 bitvec to specify dumps prior to 4031 error
_4031_dump_interval 300 Dump 4031 error once for each n-second interval
_4031_max_dumps 100 Maximum number of 4031 dumps for this process
_4031_sga_dump_interval 3600 Dump 4031 SGA heapdump error once for each n-second interval
_4031_sga_max_dumps 10 Maximum number of SGA heapdumps
_NUMA_instance_mapping Not specified Set of nodes that this instance should run on
_NUMA_pool_size Not specified aggregate size in bytes of NUMA pool
_PX_use_large_pool FALSE Use Large Pool as source of PX buffers
_UTL_FILE_FOLLOW_SYMLINKS FALSE UTL_FILE backout event which allows UTL_FILE to open symlinks
__db_cache_size 314572800 Actual size of DEFAULT buffer pool for standard block size buffers
__dg_broker_service_names pdb11_XPT service names for broker use
__java_pool_size 20971520 Actual size in bytes of java pool
__large_pool_size 4194304 Actual size in bytes of large pool
__oracle_base /u01/app/oracle ORACLE_BASE
__pga_aggregate_target 209715200 Current target size for the aggregate PGA memory consumed
__sga_target 629145600 Actual size of SGA
__shared_io_pool_size 0 Actual size of shared IO pool
__shared_pool_size 281018368 Actual size in bytes of shared pool
__streams_pool_size 0 Actual size in bytes of streams pool
_abort_recovery_on_join FALSE if TRUE, abort recovery on join reconfigurations
_accept_versions List of parameters for rolling operation
_active_standby_fast_reconfiguration TRUE if TRUE optimize dlm reconfiguration for active/standby OPS
_adaptive_direct_read TRUE Adaptive Direct Read
_adaptive_fetch_enabled TRUE enable/disable adaptive fetch in parallel group by
_add_col_optim_enabled TRUE Allows new add column optimization
_add_stale_mv_to_dependency_list TRUE add stale mv to dependency list
_addm_auto_enable TRUE governs whether ADDM gets run automatically after every AWR snapshot
_addm_skiprules comma-separated list of ADDM nodes to skip
_addm_version_check TRUE governs whether ADDM checks the input AWR snapshot version
_adjust_literal_replacement FALSE If TRUE, we will adjust the SQL/PLUS output
_affinity_on TRUE enable/disable affinity at run time
_aiowait_timeouts 100 Number of aiowait timeouts before error is reported
_alert_expiration 604800 seconds before an alert message is moved to exception queue
_alert_message_cleanup 1 Enable Alert Message Cleanup
_alert_message_purge 1 Enable Alert Message Purge
_alert_post_background 1 Enable Background Alert Posting
_all_shared_dblinks treat all dblinks as shared
_allocate_creation_order FALSE should files be examined in creation order during allocation
_allocation_update_interval 3 interval at which successful search in L1 should be updated
_allow_commutativity TRUE allow for commutativity of +, * when comparing expressions
_allow_drop_snapshot_standby_grsp FALSE Allow dropping snapshot standby guaranteed restore point
_allow_error_simulation FALSE Allow error simulation for testing
_allow_level_without_connect_by FALSE allow level without connect by
_allow_read_only_corruption FALSE allow read-only open even if database is corrupt
_allow_resetlogs_corruption FALSE allow resetlogs even if it will cause corruption
_allow_sage_attr TRUE Allow checking Disk Group SAGE Attr
_allow_terminal_recovery_corruption FALSE Finish terminal recovery even if it may cause corruption
_alternate_iot_leaf_block_split_points TRUE enable alternate index-organized table leaf-block split-points
_always_anti_join CHOOSE always use this method for anti-join when possible
_always_semi_join CHOOSE always use this method for semi-join when possible
_always_star_transformation FALSE always favor use of star transformation
_app_ctx_vers FALSE enable app ctx versioning
_aq_tm_scanlimit 0 scan limit for Time Managers to clean up IOT
_arch_corrupted_redo_log 0 Variable to simulate corruption errors during archivals
_arch_io_slaves 0 ARCH I/O slaves
_array_update_vector_read_enabled FALSE Enable array update vector read
_ash_disk_filter_ratio 10 Ratio of the number of in-memory samples to the number of samples actually written to disk
_ash_disk_write_enable TRUE To enable or disable Active Session History flushing
_ash_dummy_test_param 0 Oracle internal dummy ASH parameter used ONLY for testing!
_ash_eflush_trigger 66 The percentage above which if the in-memory ASH is full the emergency flusher will be triggered
_ash_enable TRUE To enable or disable Active Session sampling and flushing
_ash_min_mmnl_dump 90 Minimum Time interval passed to consider MMNL Dump
_ash_sample_all FALSE To enable or disable sampling every connected session including ones waiting for idle waits
_ash_sampling_interval 1000 Time interval between two successive Active Session samples in millisecs
_ash_size 1048618 To set the size of the in-memory Active Session History buffers
_asm_acd_chunks 1 initial ACD chunks created
_asm_allow_only_raw_disks TRUE Discovery only raw devices
_asm_allow_resilver_corruption FALSE Enable disk resilvering for external redundancy
_asm_ausize 1048576 allocation unit size
_asm_blksize 4096 metadata block size
_asm_compatibility 10.1 default ASM compatibility level
_asm_dbmsdg_nohdrchk FALSE dbms_diskgroup.checkfile does not check block headers
_asm_disk_repair_time 14400 seconds to wait before dropping a failing disk
_asm_emulmax 10000 max number of concurrent disks to emulate I/O errors
_asm_emultimeout 0 timeout before emulation begins (in 3s ticks)
_asm_kfdpevent 0 KFDP event
_asm_kfioevent 0 KFIO event
_asm_libraries ufs library search order for discovery
_asm_maxio 1048576 Maximum size of individual I/O request
_asm_repairquantum 60 quantum (in 3s) used to compute elapsed time for disk drop
_asm_runtime_capability_volume_support FALSE runtime capability for volume support returns supported
_asm_skip_resize_check FALSE skip the checking of the clients for s/w compatibility for resize
_asm_stripesize 131072 ASM file stripe size
_asm_stripewidth 8 ASM file stripe width
_asm_wait_time 18 Max/imum time to wait before asmb exits
_asmlib_test 0 Osmlib test event
_asmsid asm ASM instance id
_assm_default TRUE ASSM default
_async_recovery_claims TRUE if TRUE, issue recovery claims asynchronously
_async_recovery_reads TRUE if TRUE, issue recovery reads asynchronously
_async_ts_threshold 1 check tablespace thresholds asynchronously
_auto_assign_cg_for_sessions FALSE auto assign CGs for sessions
_automatic_maintenance_test 0 Enable AUTOTASK Test Mode
_automemory_broker_interval 3 memory broker statistics gathering interval for auto memory
_autotask_max_window 480 Maximum Logical Maintenance Window Length in minutes
_autotask_min_window 15 Minimum Maintenance Window Length in minutes
_autotune_gtx_idle_time 600 idle time to trigger auto-shutdown a gtx background process
_autotune_gtx_interval 5 interval to autotune global transaction background processes
_autotune_gtx_threshold 60 auto-tune threshold for degree of global transaction concurrency
_avoid_prepare TRUE if TRUE, do not prepare a buffer when the master is local
_aw_row_source_enabled TRUE Enables AW Row Source instead of collection iterator
_awr_corrupt_mode FALSE AWR Corrupt Mode
_awr_disabled_flush_tables Disable flushing of specified AWR tables
_awr_flush_threshold_metrics TRUE Enable/Disable Flushing AWR Threshold Metrics
_awr_flush_workload_metrics FALSE Enable/Disable Flushing AWR Workload Metrics
_awr_mmon_cpuusage TRUE Enable/disable AWR MMON CPU Usage Tracking
_awr_restrict_mode FALSE AWR Restrict Mode
_awr_sql_child_limit 200 Setting for AWR SQL Child Limit
_b_tree_bitmap_plans TRUE enable the use of bitmap plans for tables w. only B-tree indexes
_backup_disk_io_slaves 0 BACKUP Disk I/O slaves
_backup_encrypt_opt_mode 4294967294 specifies encryption block optimization mode
_backup_io_pool_size 1048576 memory to reserve from the large pool
_backup_kgc_bufsz 0 specifies buffer size to be used by BZIP2 compression
_backup_kgc_memlevel 8 specifies memory level for ZLIB compression
_backup_kgc_niters 0 specifies number of iterations done by BZIP2 compression
_backup_kgc_perflevel 1 specifies compression (performance) level for ZLIB compression
_backup_kgc_scheme ZLIB specifies compression scheme
_backup_kgc_type 0 specifies compression type used by kgc BZIP2 compression
_backup_kgc_windowbits 15 specifies window size for ZLIB compression
_backup_ksfq_bufcnt 0 number of the ksfq buffers used for backup/restore
_backup_ksfq_bufcnt_max 0 maximum number of the ksfq buffer used for backup/restore
_backup_ksfq_bufsz 0 size of the ksfq buffer used for backup/restore
_backup_max_gap_size 4294967294 largest gap in an incremental/optimized backup buffer, in bytes
_bct_bitmaps_per_file 8 number of bitmaps to store for each datafile
_bct_buffer_allocation_max 104857600 maximum size of all change tracking buffer allocations, in bytes
_bct_buffer_allocation_min_extents 1 mininum number of extents to allocate per buffer allocation
_bct_buffer_allocation_size 2097152 size of one change tracking buffer allocation, in bytes
_bct_chunk_size 0 change tracking datafile chunk size, in bytes
_bct_crash_reserve_size 262144 change tracking reserved crash recovery SGA space, in bytes
_bct_file_block_size 0 block size of change tracking file, in bytes
_bct_file_extent_size 0 extent size of change tracking file, in bytes
_bct_fixtab_file change tracking file for fixed tables
_bct_initial_private_dba_buffer_size 0 initial number of entries in the private change tracking dba buffers
_bct_public_dba_buffer_size 0 total size of all public change tracking dba buffers, in bytes
_bitmap_or_improvement_enabled TRUE controls extensions to partition pruning for general predicates
_block_change_tracking TRUE change tracking possible
_blocking_sess_graph_cache_size blocking session graph cache size in bytes
_blocks_per_cache_server 64 number of consecutive blocks per global cache server
_bloom_filter_debug 0 debug level for bloom filtering
_bloom_filter_enabled TRUE enables or disables bloom filter
_bloom_predicate_enabled FALSE enables or disables bloom filter predicate pushdown
_bloom_pruning_enabled TRUE Enable partition pruning using bloom filtering
_bloom_vector_elements 0 number of elements in a bloom filter vector
_bsln_adaptive_thresholds_enabled TRUE Adaptive Thresholds Enabled
_bt_mmv_query_rewrite_enabled TRUE allow rewrites with multiple MVs and base tables
_buffer_busy_wait_timeout 100 buffer busy wait time in centiseconds
_buffered_publisher_flow_control_threshold 0 Flow control threshold for buffered publishers except capture
_bufq_stop_flow_control FALSE Stop enforcing flow control for buffered queues
_build_deferred_mv_skipping_mvlog_update FALSE DEFERRED MV creation skipping MV log setup update
_bump_highwater_mark_count 0 how many blocks should we allocate per free list on advancing HWM
_bwr_for_flushed_pi TRUE if TRUE, generate a BWR for a flushed PI
_cache_stats_monitor FALSE if TRUE, enable cache stats monitoring
_capture_buffer_size 65536 To set the size of the PGA I/O recording buffers
_capture_publisher_flow_control_threshold 0 Flow control threshold for capture publishers
_case_sensitive_logon TRUE case sensitive logon enabled
_cgs_reconfig_timeout 1000 CGS reconfiguration timeout interval
_cgs_send_timeout 300 CGS send timeout value
_cgs_tickets 1000 CGS messaging tickets
_check_block_after_checksum TRUE perform block check after checksum if both are turned on
_check_block_new_invariant_for_flashback FALSE check block new invariant for flashback
_check_ts_threshold 0 check tablespace thresholds
_cleanup_rollback_entries 100 no. of undo entries to apply per transaction cleanup
_client_result_cache_bypass FALSE bypass the client result cache
_close_cached_open_cursors FALSE close cursors cached by PL/SQL at each commit
_cluster_library clss cluster library selection
_clusterwide_global_transactions TRUE enable/disable clusterwide global transactions
_collapse_wait_history FALSE collapse wait history
_collect_undo_stats TRUE Collect Statistics v$undostat
_column_compression_factor 0 Column compression ratio
_column_elimination_off FALSE turn off predicate-only column elimination
_column_tracking_level 1 column usage tracking
_compilation_call_heap_extent_size 16384 Size of the compilation call heaps extents
_complex_view_merging TRUE enable complex view merging
_compression_above_cache 0 number of recompression above cache for sanity check
_compression_advisor 0 Compression advisor
_compression_chain 50 percentage of chained rows allowed for Compression
_controlfile_block_size 0 control file block size in bytes
_controlfile_enqueue_dump FALSE dump the system states after controlfile enqueue timeout
_controlfile_enqueue_holding_time 780 control file enqueue max holding time in seconds
_controlfile_enqueue_timeout 900 control file enqueue timeout in seconds
_controlfile_section_init_size control file initial section size
_controlfile_section_max_expand control file max expansion rate
_controlfile_update_check OFF controlfile update sanity check
_convert_set_to_join FALSE enables conversion of set operator to join
_coord_message_buffer 0 parallel recovery coordinator side extra message buffer size
_corrupted_rollback_segments corrupted undo segment list
_cost_equality_semi_join TRUE enables costing of equality semi-join
_cp_num_hash_latches 1 connection pool number of hash latches
_cpu_to_io 0 divisor for converting CPU cost to I/O cost
_cr_grant_global_role TRUE if TRUE, grant lock for CR requests when block is in global role
_cr_grant_local_role AUTO turn 3-way CR grants off, make it automatic, or turn it on
_cr_server_log_flush TRUE if TRUE, flush redo log before serving a CR buffer
_cursor_bind_capture_area_size 400 maximum size of the cursor bind capture area
_cursor_bind_capture_interval 900 interval (in seconds) between two bind capture for a cursor
_cursor_db_buffers_pinned 178 additional number of buffers a cursor can pin at once
_cursor_features_enabled 2 Shared cursor features enabled bits.
_cursor_plan_enabled TRUE enable collection and display of cursor plans
_cursor_plan_hash_version 1 version of cursor plan hash value
_cursor_plan_unparse_enabled TRUE enables/disables using unparse to build projection/predicates
_cursor_stats_bucket 15 Hash table buckets for cursor stats (2^).
_cursor_stats_heap 4 Heaps/latches for cursor stats.
_cvw_enable_weak_checking TRUE enable weak view checking
_db_aging_cool_count 1 Touch count set when buffer cooled
_db_aging_freeze_cr FALSE Make CR buffers always be too cold to keep in cache
_db_aging_hot_criteria 2 Touch count which sends a buffer to head of replacement list
_db_aging_stay_count 0 Touch count set when buffer moved to head of replacement list
_db_aging_touch_time 3 Touch count which sends a buffer to head of replacement list
_db_always_check_system_ts TRUE Always perform block check and checksum for System tablespace
_db_block_adjcheck TRUE adjacent cache buffer checks – low blkchk overwrite parameter
_db_block_adjchk_level 0 adjacent cache buffer check level
_db_block_align_direct_read TRUE Align Direct Reads
_db_block_bad_write_check FALSE enable bad write checks
_db_block_buffers 27060 Number of database blocks cached in memory: hidden parameter
_db_block_cache_clone FALSE Always clone data blocks on get (for debugging)
_db_block_cache_history 0 buffer header tracing (non-zero only when debugging)
_db_block_cache_history_level 2 buffer header tracing level
_db_block_cache_num_umap 0 number of unmapped buffers (for tracking swap calls on blocks)
_db_block_cache_protect FALSE protect database blocks (true only when debugging)
_db_block_cache_protect_internal 0 protect database blocks (for strictly internal use only)
_db_block_check_for_debug FALSE Check more and dump block before image for debugging
_db_block_check_objtyp TRUE check objd and typ on cache disk read
_db_block_corruption_recovery_threshold 5 threshold number of block recovery attempts
_db_block_do_full_mbreads FALSE do full block read even if some blocks are in cache
_db_block_hash_buckets 65536 Number of database block hash buckets
_db_block_hash_latches 2048 Number of database block hash latches
_db_block_header_guard_level 0 number of extra buffer headers to use as guard pages
_db_block_hi_priority_batch_size 0 Fraction of writes for high priority reasons
_db_block_known_clean_pct 2 Initial Percentage of buffers to maintain known clean
_db_block_lru_latches 8 number of lru latches
_db_block_max_cr_dba 6 Maximum Allowed Number of CR buffers per dba
_db_block_max_scan_pct 40 Percentage of buffers to inspect when looking for free
_db_block_med_priority_batch_size 0 Fraction of writes for medium priority reasons
_db_block_numa 1 Number of NUMA nodes
_db_block_prefetch_fast_longjumps_enabled TRUE Batched IO enable fast longjumps
_db_block_prefetch_limit 0 Prefetch limit in blocks
_db_block_prefetch_override 0 Prefetch force override in blocks
_db_block_prefetch_private_cache_enabled TRUE Batched IO enable private cache
_db_block_prefetch_quota 10 Prefetch quota as a percent of cache size
_db_block_prefetch_skip_reading_enabled TRUE Batched IO enable skip reading buffers
_db_block_table_scan_buffer_size 4194304 Size of shared table scan read buffer
_db_block_temp_redo FALSE generate redo for temp blocks
_db_block_trace_protect FALSE trace buffer protect calls
_db_block_vlm_check FALSE check of rvlm mapping leaks (for debugging)
_db_block_vlm_leak_threshold 3 Threshold for allowable vlm leaks
_db_blocks_per_hash_latch Number of blocks per hash latch
_db_cache_advice_batch_size 128 cache advisory simulation batch size
_db_cache_advice_sample_factor 4 cache advisory sampling factor
_db_cache_crx_check FALSE check for costly crx examination functions
_db_cache_pre_warm TRUE Buffer Cache Pre-Warm Enabled : hidden parameter
_db_cache_process_cr_pin_max maximum number of cr pins a process may have
_db_change_notification_enable TRUE enable db change notification
_db_disable_temp_encryption FALSE Diable Temp Encryption for Spills
_db_fast_obj_check FALSE enable fast object drop sanity check
_db_fast_obj_ckpt TRUE enable fast object checkpoint
_db_fast_obj_truncate TRUE enable fast object truncate
_db_file_direct_io_count 1048576 Sequential I/O buf size
_db_file_exec_read_count 128 multiblock read count for regular clients
_db_file_format_io_buffers 4 Block formatting I/O buf count
_db_file_noncontig_mblock_read_count 11 number of noncontiguous db blocks to be prefetched
_db_file_optimizer_read_count 8 multiblock read count for regular clients
_db_handles 750 System-wide simultaneous buffer operations
_db_handles_cached 5 Buffer handles cached each process
_db_hot_block_tracking FALSE track hot blocks for hash latch contention
_db_index_block_checking TRUE index block checking override parameter
_db_large_dirty_queue 25 Number of buffers which force dirty queue to be written
_db_lost_write_checking FALSE Enable scn based lost write detection mechanism
_db_mttr_advice ON MTTR advisory
_db_mttr_partitions 0 number of partitions for MTTR advisory
_db_mttr_sample_factor 64 MTTR simulation sampling factor
_db_mttr_sim_target MTTR simulation targets
_db_mttr_sim_trace_size 256 MTTR simulation trace size
_db_mttr_trace_to_alert FALSE dump trace entries to alert file
_db_noarch_disble_optim FALSE Image redo logging (NOARCHIVEMODE)
_db_num_evict_waitevents 64 number of evict wait events
_db_obj_enable_ksr TRUE enable ksr in object checkpoint/reuse
_db_percent_hot_default 50 Percent of default buffer pool considered hot
_db_percent_hot_keep 0 Percent of keep buffer pool considered hot
_db_percent_hot_recycle 0 Percent of recycle buffer pool considered hot
_db_percpu_create_cachesize 2 size of cache created per cpu in deferred cache create
_db_recovery_temporal_file_dest default database recovery temporal file location
_db_required_percent_fairshare_usage 10 percent of fairshare a processor group should always use
_db_row_overlap_checking TRUE row overlap checking override parameter for data/index blocks
_db_todefer_cache_create TRUE buffer cache deferred create
_db_writer_chunk_writes 0 Number of writes DBWR should wait for
_db_writer_coalesce_area_size 2293760 Size of memory allocated to dbwriter for coalescing writes
_db_writer_coalesce_write_limit 131072 Limit on size of coalesced write
_db_writer_flush_imu TRUE If FALSE, DBWR will not downgrade IMU txns for AGING
_db_writer_histogram_statistics FALSE maintain dbwr histogram statistics in x$kcbbhs
_db_writer_max_writes 0 Max number of outstanding DB Writer IOs
_db_writer_nomemcopy_coalesce FALSE Enable DBWR no-memcopy coalescing
_db_writer_verify_writes FALSE Enable lost write detection mechanism
_dbg_proc_startup FALSE debug process startup
_dbms_sql_security_level 1 Security level in DBMS_SQL
_dbwr_async_io TRUE Enable dbwriter asynchronous writes
_dbwr_scan_interval 300 dbwriter scan interval
_dbwr_tracing 0 Enable dbwriter tracing
_dde_flood_control_init TRUE Initialize Flood Control at database open
_dead_process_scan_interval 60 PMON dead process scan interval
_deadlock_diagnostic_level 2 automatic deadlock resolution diagnostics level
_deadlock_resolution_incidents_enabled TRUE create incidents during deadlock resolution
_deadlock_resolution_level 1 automatic deadlock resolution level
_deadlock_resolution_min_wait_timeout_secs 60 the minimum wait timeout required for deadlock resolution
_deadlock_resolution_signal_process_thresh_secs 60 the amount of time given to process a deadlock resolution signal
_dedicated_server_poll_count 10 dedicated server poll count
_dedicated_server_post_wait FALSE dedicated server post/wait
_dedicated_server_post_wait_call FALSE dedicated server post/wait call
_default_encrypt_alg 0 default encryption algorithm
_default_non_equality_sel_check TRUE sanity check on default selectivity for like/range predicate
_defer_log_boundary_ckpt TRUE defer media recovery checkpoint at log boundary
_defer_log_count 2 Number of log boundaries media recovery checkpoint lags behind
_delay_index_maintain TRUE delays index maintenance until after MV is refreshed
_desired_readmem_rate 70 The desired percentage of redo reading from memory
_diag_adr_auto_purge TRUE Enable/disable ADR MMON Auto Purging
_diag_adr_enabled TRUE Parameter to enable/disable Diag ADR
_diag_adr_test_param 0 Test parameter for Diagnosability
_diag_backward_compat TRUE Backward Compatibility for Diagnosability
_diag_cc_enabled TRUE Parameter to enable/disable Diag Call Context
_diag_conf_cap_enabled TRUE Parameter to enable/disable Diag Configuration Capture
_diag_daemon TRUE start DIAG daemon
_diag_dde_async_age_limit 300 diag dde async actions: message age limit (in seconds)
_diag_dde_async_cputime_limit 300 diag dde async actions: action cputime limit (in seconds)
_diag_dde_async_mode 1 diag dde async actions: dispatch mode
_diag_dde_async_msg_capacity 1024 diag dde async actions: message buffer capacity
_diag_dde_async_msgs 50 diag dde async actions: number of preallocated message buffers
_diag_dde_async_process_rate 5 diag dde async actions: message processing rate – per loop
_diag_dde_async_runtime_limit 900 diag dde async actions: action runtime limit (in seconds)
_diag_dde_async_slaves 5 diag dde async actions: max number of concurrent slave processes
_diag_dde_enabled TRUE enable DDE handling of critical errors
_diag_dde_fc_enabled TRUE Parameter to enable/disable Diag Flood Control
_diag_dde_fc_implicit_time 0 Override Implicit Error Flood Control time parameter
_diag_dde_fc_macro_time 0 Override Macro Error Flood Control time parameter
_diag_dde_inc_proc_delay 1 The minimum delay between two MMON incident sweeps (minutes)
_diag_diagnostics TRUE Turn off diag diagnostics
_diag_dump_timeout 30 timeout parameter for SYNC dump
_diag_hm_rc_enabled TRUE Parameter to enable/disable Diag HM Reactive Checks
_diag_hm_tc_enabled FALSE Parameter to enable/disable Diag HM Test(dummy) Checks
_diag_uts_control 0 UTS control parameter
_dimension_skip_null TRUE control dimension skip when null feature
_direct_path_insert_features 0 disable direct path insert features
_disable_12751 FALSE disable policy timeout error (ORA-12751)
_disable_adaptive_shrunk_aggregation FALSE adaptive shrunk aggregation
_disable_autotune_gtx FALSE disable autotune global transaction background processes
_disable_datalayer_sampling FALSE disable datalayer sampling
_disable_duplex_link TRUE Turn off connection duplexing
_disable_fast_aggregation FALSE fast aggregation
_disable_fast_validate FALSE disable PL/SQL fast validation
_disable_fastopen FALSE Do Not Use Fastopen
_disable_fba_qrw 0 disable flashback archiver query rewrite
_disable_fba_wpr 0 disable flashback archiver wait for prepared transactions
_disable_file_locks FALSE disable file locks for control, data, redo log files
_disable_flashback_archiver 0 disable flashback archiver
_disable_flashback_wait_callback FALSE Disable flashback wait callback
_disable_function_based_index FALSE disable function-based index matching
_disable_health_check FALSE Disable Health Check
_disable_highres_ticks FALSE disable high-res tick counter
_disable_image_check FALSE Disable Oracle executable image checking
_disable_incremental_checkpoints FALSE Disable incremental checkpoints for thread recovery
_disable_incremental_recovery_ckpt FALSE Disable incremental recovery checkpoint mechanism
_disable_index_block_prefetching FALSE disable index block prefetching
_disable_instance_params_check FALSE disable instance type check for ksp
_disable_interface_checking FALSE disable interface checking at startup
_disable_kcb_flashback_blocknew_opt FALSE Disable KCB flashback block new optimization
_disable_kcbhxor_osd FALSE disable kcbh(c)xor OSD functionality
_disable_kcbl_flashback_blocknew_opt FALSE Disable KCBL flashback block new optimization
_disable_latch_free_SCN_writes_via_32cas FALSE disable latch-free SCN writes using 32-bit compare & swap
_disable_latch_free_SCN_writes_via_64cas FALSE disable latch-free SCN writes using 64-bit compare & swap
_disable_logging FALSE Disable logging
_disable_metrics_group 0 Disable Metrics Group (or all Metrics Groups)
_disable_multiple_block_sizes FALSE disable multiple block size support (for debugging)
_disable_odm FALSE disable odm feature
_disable_parallel_conventional_load FALSE Disable parallel conventional loads
_disable_read_only_open_dict_check FALSE Disable read-only open dictionary check
_disable_rebalance_space_check FALSE disable space usage checks for storage reconfiguration
_disable_recoverable_recovery FALSE Disable the new recoverable recovery mechanism
_disable_recovery_read_skip FALSE Disable the read optimization during media recovery
_disable_sample_io_optim FALSE disable row sampling IO optimization
_disable_savepoint_reset FALSE disable the fix for bug 1402161
_disable_sec_ticks FALSE disable low-res (sec) counter
_disable_selftune_checkpointing FALSE Disable self-tune checkpointing
_disable_streams_pool_auto_tuning FALSE disable streams pool auto tuning
_disable_sun_rsm TRUE Disable IPC OSD support for Sun RSMAPI
_disable_system_state 4294967294 disable system state dump
_disable_thread_internal_disable FALSE Disable thread internal disable feature
_disable_txn_alert 0 disable txn layer alert
_disable_vktm FALSE disable vktm process
_disable_wait_stack FALSE Disable wait stack
_discrete_transactions_enabled FALSE enable OLTP mode
_diskmon_pipe_name DiSKMon skgznp pipe name
_dispatcher_rate_scale scale to display rate statistic (100ths of a second)
_dispatcher_rate_ttl time-to-live for rate statistic (100ths of a second)
_distinct_view_unnesting FALSE enables unnesting of in subquery into distinct view
_distributed_recovery_connection_hold_time 200 number of seconds RECO holds outbound connections open
_dlmtrace Trace string of global enqueue type(s)
_dm_max_shared_pool_pct 1 max percentage of the shared pool to use for a mining model
_dml_monitoring_enabled TRUE enable modification monitoring
_domain_index_batch_size 2000 maximum number of rows from one call to domain index fetch routine
_domain_index_dml_batch_size 200 maximum number of rows for one call to domain index dml routines
_dra_bmr_number_threshold 1000 Maximum number of BMRs that can be done to a file
_dra_bmr_percent_threshold 10 Maximum percentage of blocks in a file that can be BMR-ed
_dra_enable_offline_dictionary TRUE Enable the periodic creation of the offline dictionary for DRA
_drop_table_granule 256 drop_table_granule
_drop_table_optimization_enabled TRUE reduce SGA memory use during drop of a partitioned table
_ds_iocount_iosize 6553664 Dynamic Sampling Service defaults: #IOs and IO Size
_dss_cache_flush FALSE enable full cache flush for parallel execution
_dtree_area_size 131072 size of Decision Tree Classification work area
_dtree_binning_enabled TRUE Decision Tree Binning Enabled
_dtree_bintest_id 0 Decision Tree Binning Test ID
_dtree_compressbmp_enabled TRUE Decision Tree Using Compressed Bitmaps Enabled
_dtree_max_surrogates 1 maximum number of surrogates
_dtree_pruning_enabled TRUE Decision Tree Pruning Enabled
_dummy_instance FALSE dummy instance started by RMAN
_dump_common_subexpressions FALSE dump common subexpressions
_dump_connect_by_loop_data FALSE dump connect by loop error message into trc file
_dump_cursor_heap_sizes FALSE dump comp/exec heap sizes to tryace file
_dump_interval_limit 120 trace dump time interval limit (in seconds)
_dump_max_limit 5 max number of dump within dump interval
_dump_qbc_tree 0 dump top level query parse tree to trace
_dump_rcvr_ipc TRUE if TRUE enables IPC dump at instance eviction time
_dump_system_state_scope local scope of sysstate dump during instance termination
_dump_trace_scope global scope of trace dump during a process crash
_dynamic_rls_policies TRUE rls policies are dynamic
_dynamic_stats_threshold 30 delay threshold (in seconds) between sending statistics messages
_edition_based_redefinition FALSE enable edition based redefinition
_eliminate_common_subexpr TRUE enables elimination of common sub-expressions
_emon_regular_ntfn_slaves 4 number of EMON slaves doing regular database notifications
_enable_NUMA_optimization TRUE Enable NUMA specific optimizations
_enable_automatic_maintenance 1 if 1, Automated Maintenance Is Enabled
_enable_automatic_sqltune TRUE Automatic SQL Tuning Advisory enabled parameter
_enable_block_level_transaction_recovery TRUE enable block level recovery
_enable_cscn_caching FALSE enable commit SCN caching for all transactions
_enable_ddl_wait_lock TRUE use this to turn off ddls with wait semantics
_enable_default_affinity 0 to enable default implementation of affinity osds
_enable_dml_lock_escalation TRUE enable dml lock escalation against partitioned tables if TRUE
_enable_exchange_validation_using_check TRUE use check constraints on the table for validation
_enable_fast_ref_after_mv_tbs FALSE enable fast refresh after move tablespace
_enable_hash_overflow FALSE TRUE – enable hash cluster overflow based on SIZE
_enable_hwm_sync TRUE enable HWM synchronization
_enable_list_io FALSE Enable List I/O
_enable_midtier_affinity TRUE enable midtier affinity metrics processing
_enable_nativenet_tcpip FALSE Enable skgxp driver usage for native net
_enable_obj_queues TRUE enable object queues
_enable_online_index_without_s_locking TRUE Allow online index creation algorithm without S DML lock
_enable_query_rewrite_on_remote_objs TRUE mv rewrite on remote table/view
_enable_refresh_schedule TRUE enable or disable MV refresh scheduling (revert to 9.2 behavior)
_enable_reliable_latch_waits TRUE Enable reliable latch waits
_enable_rlb TRUE enable RLB metrics processing
_enable_row_shipping TRUE use the row shipping optimization for wide table selects
_enable_scn_wait_interface TRUE use this to turn off scn wait interface in kta
_enable_separable_transactions FALSE enable/disable separable transactions
_enable_shared_pool_durations TRUE temporary to disable/enable kgh policy
_enable_shared_server_vector_io FALSE Enable shared server vector I/O
_enable_space_preallocation 3 enable space pre-allocation
_enable_spacebg TRUE enable space management background task
_enable_tablespace_alerts TRUE enable tablespace alerts
_enable_type_dep_selectivity TRUE enable type dependent selectivity estimates
_endprot_chunk_comment chk 10235 dflt chunk comment for selective overrun protection
_endprot_heap_comment hp 10235 dflt heap comment for selective overrun protection
_endprot_subheaps TRUE selective overrun protection for subeheaps
_enqueue_deadlock_time_sec 5 requests with timeout <= this will not have deadlock detection
_enqueue_debug_multi_instance FALSE debug enqueue multi instance
_enqueue_hash 375 enqueue hash table length
_enqueue_hash_chain_latches 1 enqueue hash chain latches
_enqueue_locks 2260 locks for managed enqueues
_enqueue_resources 968 resources for enqueues
_evolve_plan_baseline_report_level TYPICAL Level of detail to show in plan verification/evolution report
_evt_system_event_propagation TRUE disable system event propagation
_expand_aggregates TRUE expand aggregates
_explain_rewrite_mode FALSE allow additional messages to be generated during explain rewrite
_extended_pruning_enabled TRUE do runtime pruning in iterator if set to TRUE
_fair_remote_cvt FALSE if TRUE enables fair remote convert
_fairness_threshold 4 number of times to CR serve before downgrading lock
_fast_dual_enabled TRUE enable/disable fast dual
_fast_full_scan_enabled TRUE enable/disable index fast full scan
_fastpin_enable 1 enable reference count based fast pins
_fbda_busy_percentage 0 flashback archiver busy percentage
_fbda_inline2_percentage 0 flashback archiver full inline percentage
_fbda_inline_percentage 0 flashback archiver inline percentage
_fg_iorm_slaves 1 ForeGround I/O slaves for IORM
_fg_log_checksum TRUE Checksum redo in foreground process
_fic_algorithm_set automatic Set Frequent Itemset Counting Algorithm
_fic_area_size 131072 size of Frequent Itemset Counting work area
_fic_max_length 20 Frequent Itemset Counting Maximum Itemset Length
_fic_min_bmsize 1024 Frequent Itemset Counting Minimum BITMAP Size
_fic_outofmem_candidates FALSE Frequent Itemset Counting Out Of Memory Candidates Generation
_fifth_spare_parameter fifth spare parameter – string
_filemap_dir FILEMAP directory
_first_k_rows_dynamic_proration TRUE enable the use of dynamic proration of join cardinalities
_first_spare_parameter first spare parameter – integer
_fix_control bug fix control parameter
_flashback_allow_noarchivelog FALSE Allow enabling flashback on noarchivelog database
_flashback_archiver_partition_size 0 flashback archiver table partition size
_flashback_barrier_interval 1800 Flashback barrier interval in seconds
_flashback_copy_latches 10 Number of flashback copy latches
_flashback_format_chunk_mb 4 Chunk mega-bytes for formatting flashback logs using sync write
_flashback_format_chunk_mb_dwrite 16 Chunk mega-bytes for formatting flashback logs using delayed write
_flashback_fuzzy_barrier TRUE Use flashback fuzzy barrier
_flashback_generation_buffer_size 4194304 flashback generation buffer size
_flashback_hint_barrier_percent 20 Flashback hint barrier percent
_flashback_log_io_error_behavior 0 Specify Flashback log I/O error behavior
_flashback_log_min_size 100 Minimum flashback log size
_flashback_log_size 1000 Flashback log size
_flashback_logfile_enqueue_timeout 600 flashback logfile enqueue timeout for opens
_flashback_marker_cache_enabled TRUE Enable flashback database marker cache
_flashback_marker_cache_size 328 Size of flashback database marker cache
_flashback_max_log_size 0 Maximum flashback log size in bytes (OS limit)
_flashback_max_n_log_per_thread 2048 Maximum number of flashback logs per flashback thread
_flashback_max_standby_sync_span 900 Maximum time span between standby recovery sync for flashback
_flashback_n_log_per_thread 128 Desired number of flashback logs per flashback thread
_flashback_standby_barrier_interval 1800 Flashback standby barrier interval in seconds
_flashback_verbose_info FALSE Print verbose information about flashback database
_flashback_write_max_loop_limit 10 Flashback writer loop limit before it returns
_force_datefold_trunc FALSE force use of trunc for datefolding rewrite
_force_hsc_compress FALSE compress all new created tables
_force_oltp_compress FALSE OLTP Compress all new created tables
_force_rewrite_enable FALSE control new query rewrite features
_force_slave_mapping_intra_part_loads FALSE Force slave mapping for intra partition loads
_force_temptables_for_gsets FALSE executes concatenation of rollups using temp tables
_force_tmp_segment_loads FALSE Force tmp segment loads
_forwarded_2pc_threshold 10 auto-tune threshold for two-phase commit rate across RAC instances
_fourth_spare_parameter fourth spare parameter – string
_full_pwise_join_enabled TRUE enable full partition-wise join when TRUE
_gby_hash_aggregation_enabled TRUE enable group-by and aggregation using hash scheme
_gby_onekey_enabled TRUE enable use of one comparison of all group by keys
_gc_affinity_locking TRUE if TRUE, enable object affinity
_gc_affinity_locks TRUE if TRUE, get affinity locks
_gc_affinity_ratio 50 dynamic object affinity ratio
_gc_async_memcpy FALSE if TRUE, use async memcpy
_gc_bypass_readers TRUE if TRUE, modifications bypass readers
_gc_check_bscn TRUE if TRUE, check for stale blocks
_gc_coalesce_recovery_reads TRUE if TRUE, coalesce recovery reads
_gc_defer_time 3 how long to defer down converts for hot buffers
_gc_dissolve_undo_affinity FALSE if TRUE, dissolve undo affinity after an offline
_gc_element_percent 110 global cache element percent
_gc_global_checkpoint_scn TRUE if TRUE, enable global checkpoint scn
_gc_global_lru AUTO turn global lru off, make it automatic, or turn it on
_gc_initiate_undo_affinity TRUE if TRUE, initiate undo affinity after an online
_gc_integrity_checks 1 set the integrity check level
_gc_keep_recovery_buffers TRUE if TRUE, make recovery buffers current
_gc_latches 8 number of latches per LMS process
_gc_long_query_threshold 0 threshold for long running query
_gc_maximum_bids 0 maximum number of bids which can be prepared
_gc_policy_minimum 1500 dynamic object policy minimum activity per minute
_gc_policy_time 10 how often to make object policy decisions in minutes
_gc_read_mostly_locking TRUE if TRUE, enable read-mostly locking
_gc_statistics TRUE if TRUE, kcl statistics are maintained
_gc_transfer_ratio 2 dynamic object read-mostly transfer ratio
_gc_undo_affinity TRUE if TRUE, enable dynamic undo affinity
_gc_undo_block_disk_reads TRUE if TRUE, enable undo block disk reads
_gc_use_cr TRUE if TRUE, allow CR pins on PI and WRITING buffers
_gc_vector_read TRUE if TRUE, vector read current buffers
_gc_voluntary_down_convert_obj 0 object number for voluntary down-convert
_gcs_fast_reconfig TRUE if TRUE, enable fast reconfiguration for gcs locks
_gcs_latches 0 number of gcs resource hash latches to be allocated per LMS process
_gcs_process_in_recovery TRUE if TRUE, process gcs requests during instance recovery
_gcs_res_per_bucket 16 number of gcs resource per hash bucket
_gcs_resources number of gcs resources to be allocated
_gcs_shadow_locks number of pcm shadow locks to be allocated
_gcs_testing 0 GCS testing parameter
_generalized_pruning_enabled TRUE controls extensions to partition pruning for general predicates
_ges_dd_debug 1 if 1 or higher enables GES deadlock detection debug diagnostics
_ges_diagnostics TRUE if TRUE enables GES diagnostics
_ges_health_check 1 if greater than 0 enables GES system health check
_global_hang_analysis_interval_secs 10 the interval at which global hang analysis is run
_globalindex_pnum_filter_enabled TRUE enables filter for global index with partition extended syntax
_groupby_nopushdown_cut_ratio 3 groupby nopushdown cut ratio
_groupby_orderby_combine 5000 groupby/orderby don’t combine threshold
_gs_anti_semi_join_allowed TRUE enable anti/semi join for the GS query
_hang_analysis_num_call_stacks 3 hang analysis num call stacks
_hang_detection 60 Hang Management detection interval
_hang_resolution FALSE Hang Management hang resolution
_hard_protection FALSE if TRUE enable H.A.R.D specific format changes
_hash_join_enabled TRUE enable/disable hash join
_hash_multiblock_io_count 0 number of blocks hash join will read/write at once
_heur_deadlock_resolution_secs 0 the heuristic wait time per node for deadlock resolution
_high_priority_processes LMS*|VKTM High Priority Process Name Mask
_high_server_threshold 0 high server thresholds
_hj_bit_filter_threshold 50 hash-join bit filtering threshold (0 always enabled)
_hm_analysis_oradebug_node_dump_level 0 the oradebug node dump level for hang manager hang analysis
_hm_analysis_oradebug_sys_dump_level 0 the oradebug system state level for hang manager hang analysis
_hm_analysis_output_disk FALSE if TRUE the hang manager outputs hang analysis results to disk
_hm_log_incidents FALSE Hang Manager incident logging
_hm_verification_interval 60 the hang manager verification interval
_hwm_sync_threshold 10 HWM synchronization threshold in percentage
_idl_conventional_index_maintenance TRUE enable conventional index maintenance for insert direct load
_idle_session_kill_enabled TRUE enables or disables resource manager session idle limit checks
_idxrb_rowincr 100000000 proportionality constant for dop vs. rows in index rebuild
_ignore_desc_in_index FALSE ignore DESC in indexes, sort those columns ascending anyhow
_ignore_fg_deps ignore fine-grain dependencies during invalidation
_immediate_commit_propagation TRUE if TRUE, propagate commit SCN immediately
_improved_outerjoin_card TRUE improved outer-join cardinality calculation
_improved_row_length_enabled TRUE enable the improvements for computing the average row length
_imr_active TRUE Activate Instance Membership Recovery feature
_imr_avoid_double_voting TRUE Avoid device voting for CSS reconfig during IMR
_imr_device_type controlfile Type of device to be used by IMR
_imr_disk_voting_interval 3 Maximum wait for IMR disk voting (seconds)
_imr_evicted_member_kill TRUE IMR issue evicted member kill after a wait
_imr_evicted_member_kill_wait 20 IMR evicted member kill wait time in seconds
_imr_highload_threshold IMR system highload threshold
_imr_max_reconfig_delay 300 Maximum Reconfiguration delay (seconds)
_imr_splitbrain_res_wait 600 Maximum wait for split-brain resolution (seconds)
_imr_systemload_check TRUE Perform the system load check during IMR
_imu_pools 3 in memory undo pools
_in_memory_undo TRUE Make in memory undo for top level transactions
_incremental_recovery_ckpt_min_batch 30 Minimum number of writes for incremental recovery ckpt every 3 sec
_index_join_enabled TRUE enable the use of index joins
_index_prefetch_factor 100 index prefetching factor
_init_granule_interval 10 number of granules to process for deferred cache
_init_sql_file ?/rdbms/admin/sql.bsq File containing SQL statements to execute upon database creation
_inject_startup_fault 0 inject fault in the startup code
_inline_sql_in_plsql FALSE inline SQL in PL/SQL
_insert_enable_hwm_brokered TRUE during parallel inserts high water marks are brokered
_inst_locking_period 5 period an instance can retain a newly acquired level1 bitmap
_interconnect_checksum TRUE if TRUE, checksum interconnect blocks
_intrapart_pdml_enabled TRUE Enable intra-partition updates/deletes
_intrapart_pdml_randomlocal_enabled TRUE Enable intra-partition updates/deletes with random local dist
_io_resource_manager_always_on FALSE io resource manager always on
_io_shared_pool_size 4194304 Size of I/O buffer pool from SGA
_io_slaves_disabled FALSE Do not use I/O slaves
_io_statistics TRUE if TRUE, ksfd I/O statistics are collected
_ioq_fanin_multiplier 2 IOQ miss count before a miss exception
_ior_serialize_fault 0 inject fault in the ior serialize code
_iorm_tout 1000 IORM scheduler timeout value in msec
_ioslave_batch_count 1 Per attempt IOs picked
_ioslave_issue_count 500 IOs issued before completion check
_ipc_fail_network 0 Simulate cluster network failer
_ipc_test_failover 0 Test transparent cluster network failover
_ipc_test_mult_nets 0 simulate multiple cluster networks
_job_queue_interval 5 Wakeup interval in seconds for job queue co-ordinator
_k2q_latches 0 number of k2q latches
_kcfis_fault_control 0 trace level setting for KCFIS module
_kcfis_max_appliances 40 Max. appliances in a KCFIS session
_kcfis_oss_io_size 0 KCFIS OSS I/O size
_kcfis_read_buffer_limit 0 KCFIS Read Buffer (per session) memory limit in bytes
_kcfis_trace_level 0 trace level setting for KCFIS module
_kcfis_work_set_appliances 6 Working Set of appliances in a KCFIS session
_kcl_commit TRUE if TRUE, call kjbcommit
_kcl_conservative_log_flush FALSE if TRUE, conservatively log flush before CR serving
_kcl_debug TRUE if TRUE, record le history
_kcl_index_split TRUE if TRUE, reject pings on blocks in middle of a split
_kdbl_enable_post_allocation FALSE allocate dbas after populating data buffers
_kdi_avoid_block_checking FALSE avoid index block checking on sensitive opcodes
_kdli_STOP_bsz 0 undocumented parameter for internal use only
_kdli_STOP_dba 0 undocumented parameter for internal use only
_kdli_STOP_fsz 0 undocumented parameter for internal use only
_kdli_STOP_nio 0 undocumented parameter for internal use only
_kdli_STOP_tsn 0 undocumented parameter for internal use only
_kdli_allow_corrupt TRUE allow corrupt filesystem_logging data blocks during read/write
_kdli_cache_inode TRUE cache inode state across calls
_kdli_cache_read_threshold 0 minimum lob size for cache->nocache read (0 disables heuristic)
_kdli_cache_size 8 maximum #entries in inode cache
_kdli_cache_verify FALSE verify cached inode via deserialization
_kdli_cache_write_threshold 0 minimum lob size for cache->nocache write (0 disables heuristic)
_kdli_cacheable_length 0 minimum lob length for inode cacheability
_kdli_force_cr TRUE force CR when reading data blocks of direct-write lobs
_kdli_force_cr_meta TRUE force CR when reading metadata blocks of direct-write lobs
_kdli_force_storage none force storage settings for all lobs
_kdli_full_readahead_threshold 0 maximum lob size for full readahead
_kdli_inject_assert 0 inject asserts into the inode
_kdli_inject_crash 0 inject crashes into the inode
_kdli_inline_xfm TRUE allow inline transformed lobs
_kdli_inode_preference data inline inode evolution preference (data, headless, lhb)
_kdli_itree_entries 0 #entries in lhb/itree blocks (for testing only)
_kdli_memory_protect FALSE trace accesses to inode memory outside kdli API functions
_kdli_rci_lobmap_entries 255 #entries in RCI lobmap before migration to lhb
_kdli_readahead_limit 0 shared/cached IO readahead limit
_kdli_readahead_strategy contig shared/cached IO readahead strategy
_kdli_recent_scn FALSE use recent (not dependent) scns for block format/allocation
_kdli_reshape FALSE reshape an inode to inline or headless on length truncation
_kdli_safe_callbacks TRUE invoke inode read/write callbacks safely
_kdli_sio_async TRUE asynchronous shared IO
_kdli_sio_backoff FALSE use exponential backoff when attempting SIOP allocations
_kdli_sio_bps 0 maximum blocks per IO slot
_kdli_sio_dop 2 degree-of-parallelism in the SIO keep pool
_kdli_sio_fgio TRUE reap asynchronous IO in the foreground
_kdli_sio_fileopen nodsync shared IO fileopen mode: datasync vs nodatasync vs async
_kdli_sio_flush FALSE enable shared IO pool operations
_kdli_sio_free TRUE free IO buffers when not in active use
_kdli_sio_min_read 0 shared IO pool read threshold
_kdli_sio_min_write 0 shared IO pool write threshold
_kdli_sio_nbufs 8 maximum #IO buffers to allocate per session
_kdli_sio_niods 8 maximum #IO descriptors to allocate per session
_kdli_sio_on TRUE enable shared IO pool operations
_kdli_sio_pga FALSE use PGA allocations for direct IO
_kdli_sio_pga_top FALSE PGA allocations come from toplevel PGA heap
_kdli_sio_strategy auto shared IO strategy: block vs. extent
_kdli_small_cache_limit 32 size limit of small inode cache
_kdli_sort_dbas FALSE sort dbas during chunkification
_kdli_space_cache_limit 2048 maximum size of the space cache in #blocks
_kdli_squeeze TRUE compact lobmap extents with contiguous dbas
_kdli_timer_dmp FALSE dump inode timers on session termination
_kdli_timer_trc FALSE trace inode timers to uts/tracefile
_kdli_trace 0 inode trace level
_kdlu_max_bucket_size 4194304 UTS kdlu bucket size
_kdlu_max_bucket_size_mts 131072 UTS kdlu bucket size for mts
_kdlu_trace_layer 0 UTS kdlu per-layer trace level
_kdlu_trace_session 0 UTS session dump
_kdlu_trace_system 0 UTS system dump
_kdlw_enable_ksi_locking FALSE enable ksi locking for lobs
_kdlw_enable_write_gathering TRUE enable lob write gathering for sql txns
_kdlwp_flush_threshold 4194304 WGC flush threshold in bytes
_kdlxp_cmp_subunit_size 262144 size of compression sub-unit in bytes
_kdlxp_dedup_flush_threshold 8388608 deduplication flush threshold in bytes
_kdlxp_dedup_hash_algo SHA1 secure hash algorithm for deduplication – only on SecureFiles
_kdlxp_dedup_prefix_threshold 1048576 deduplication prefix hash threshold in bytes
_kdlxp_lobcompress FALSE enable lob compression – only on SecureFiles
_kdlxp_lobdeduplicate FALSE enable lob deduplication – only on SecureFiles
_kdlxp_lobdedupvalidate TRUE enable deduplicate validate – only on SecureFiles
_kdlxp_lobencrypt FALSE enable lob encryption – only on SecureFiles
_kdlxp_min_xfm_size 32768 minimum transformation size in bytes
_kdlxp_mincmp 20 minimum comp ratio in pct – only on SecureFiles
_kdlxp_spare1 0 deduplication spare 1
_kdlxp_xfmcache TRUE enable xfm cache – only on SecureFiles
_kdt_buffering TRUE control kdt buffering for conventional inserts
_kebm_nstrikes 3 kebm # strikes to auto suspend an action
_kebm_suspension_time 82800 kebm auto suspension time in seconds
_keep_remote_column_size FALSE remote column size does not get modified
_kernel_message_network_driver FALSE kernel message network driver
_kffmap_hash_size 1024 size of kffmap_hash table
_kffmop_hash_size 2048 size of kffmop_hash table
_kfm_disable_set_fence FALSE disable set fence calls and revert to default (process fence)
_kghdsidx_count 1 max kghdsidx count
_kgl_bucket_count 9 index to the bucket count array
_kgl_debug Library cache debugging
_kgl_features_enabled 2 Library cache features enabled bits
_kgl_fixed_extents TRUE fixed extent size for library cache memory allocations
_kgl_hash_collision FALSE whether KGL hash collision is possible
_kgl_heap_size 1024 extent size for library cache heap 0
_kgl_kqr_cap_so_stacks FALSE capture stacks for library and row cache state objects
_kgl_large_heap_warning_threshold 52428800 maximum heap size before KGL writes warnings to the alert log
_kgl_latch_count 0 number of library cache latches
_kgl_message_locks 64 RAC message lock count
_kgl_min_cached_so_count 1 Minimum cached SO count. If > 1 can help find SO corruptions
_kgl_multi_instance_invalidation TRUE whether KGL to support multi-instance invalidations
_kgl_multi_instance_lock TRUE whether KGL to support multi-instance locks
_kgl_multi_instance_pin TRUE whether KGL to support multi-instance pins
_kgl_so_stack_depth 16 The depth of the stack capture for SO get or free
_kgl_time_to_wait_for_locks 15 time to wait for locks and pins before timing out
_kglsim_maxmem_percent 5 max percentage of shared pool size to be used for KGL advice
_kgsb_threshold_size 16777216 threshold size for base allocator
_kgx_latches 1024 # of mutex latches if CAS is not supported.
_kgx_spin_count 255 third spare parameter – integer
_kill_controlfile_enqueue_blocker TRUE enable killing controlfile enqueue blocker on timeout
_kill_diagnostics_timeout 60 timeout delay in seconds before killing enqueue blocker
_kill_enqueue_blocker 2 if greater than 0 enables killing enqueue blocker
_kill_java_threads_on_eoc FALSE Kill Java threads and do sessionspace migration at end of call
_kill_session_dump TRUE Process dump on kill session immediate
_kkdlgon_max_iter 20000 kkdlgon maximum number of iterations
_kkfi_trace FALSE trace expression substitution
_kks_free_cursor_stat_pct 10 percentage of cursor stats buckets to scan on each load, in 1/10th of a percent
_kks_use_mutex_pin TRUE Turning on this will make KKS use mutex for cursor pins.
_kokli_cache_size 32 Size limit of Materialized View and Object Table Lookup Cache
_kolfuseslf FALSE allow kolf to use slffopen
_kql_subheap_trace 0 tracing level for library cache subheap level pins
_ksb_disable_diagpid FALSE disable the call to ksb_diagpid
_ksb_restart_clean_time 30000 process uptime for restarts
_ksb_restart_policy_times 0, 60, 120, 240 process restart policy times in seconds
_ksd_test_param 999 KSD test parmeter
_ksdxdocmd_default_timeout_ms 30000 default timeout for internal oradebug commands
_ksdxdocmd_enabled TRUE if TRUE ksdxdocmd* invocations are enabled
_ksdxw_cini_flg 0 ksdxw context initialization flag
_ksdxw_nbufs 1000 ksdxw number of buffers in buffered mode
_ksdxw_num_pgw 10 number of watchpoints on a per-process basis
_ksdxw_num_sgw 10 number of watchpoints to be shared by all processes
_ksdxw_stack_depth 4 number of PCs to collect in the stack when watchpoint is hit
_kse_die_timeout 60000 amount of time a dying process is spared by PMON (in centi-secs)
_kse_pc_table_size 256 kse pc table cache size
_kse_signature_entries 0 number of entries in the kse stack signature cache
_kse_signature_limit 7 number of stack frames to cache per kse signature
_kse_snap_ring_size 0 ring buffer to debug internal error 17090
_ksfd_verify_write FALSE verify asynchronous writes issued through ksfd
_ksi_trace KSI trace string of lock type(s)
_ksi_trace_bucket PRIVATE memory tracing: use ksi-private or rdbms-shared bucket
_ksi_trace_bucket_size 8192 size of the KSI trace bucket
_ksmb_debug 0 ksmb debug flags
_ksmd_protect_mode off KSMD protect mode for catching stale access
_ksmg_granule_locking_status 1 granule locking status
_ksmg_granule_size 4194304 granule size in bytes
_ksmg_lock_check_interval timeout action interval in minutes
_ksmg_lock_reacquire_count 5 repeat count for acquisition of locks
_kspol_tac_timeout 5 timeouts for TAC registerd by kspol
_ksr_unit_test_processes 0 number of ksr unit test processes
_kss_quiet FALSE if TRUE access violations during kss dumps are not recorded
_ksu_diag_kill_time 5 number of seconds ksuitm waits before killing diag
_ksuitm_addon_trccmd command to execute when dead processes don’t go away
_ksuitm_dont_kill_dumper FALSE delay inst. termination to allow processes to dump
_ksv_max_spawn_fail_limit 5 bg slave spawn failure limit
_ksv_pool_hang_kill_to 0 bg slave pool terminate timeout
_ksv_pool_wait_timeout 600 bg slave pool wait limit
_ksv_spawn_control_all FALSE control all spawning of background slaves
_ksvppktmode 0 ksv internal pkt test
_ksxp_diagmode OFF set to OFF to disable automatic slowsend diagnostics
_ksxp_disable_dynamic_loading FALSE disable dynamic loadin of lib skgxp
_ksxp_disable_ipc_stats FALSE disable ipc statistics
_ksxp_init_stats_bkts 0 initial number arrays for ipc statistics
_ksxp_max_stats_bkts 0 max. arrays for ipc statistics
_ksxp_ping_enable TRUE disable dynamic loadin of lib skgxp
_ksxp_ping_polling_time 0 max. arrays for ipc statistics
_ksxp_reaping 20 tune ksxp layer reaping limit
_ksxp_reporting_process LMD0 reporting process for KSXP
_ksxp_send_timeout 300 set timeout for sends queued with the inter-instance IPC
_ksxp_skgxp_compat_library_path over-ride default location of lib skgxp compat
_ksxp_skgxp_library_path over-ride default location of lib skgxp
_ksxp_stats_mem_lmt 0 limit ipc statistics memory. this parameter is a percentage value
_ksxp_testing 0 KSXP test parameter
_ksxp_unit_test_byte_transformation FALSE enable byte transformation unit test
_ktc_debug 0 for ktc debug
_ktc_latches 0 number of ktc latches
_ktslj_segext_warning 10 segment pre-extension warning threshold in percentage
_ktspsrch_maxsc 32 maximum segments supported by space search cache
_kttext_warning 5 tablespace pre-extension warning threshold in percentage
_ktu_latches 0 number of KTU latches
_ku_trace none datapump trace parameter
_large_pool_min_alloc 16000 minimum allocation size in bytes for the large allocation pool
_last_allocation_period 5 period over which an instance can retain an active level1 bitmap
_latch_class_0 latch class 0
_latch_class_1 latch class 1
_latch_class_2 latch class 2
_latch_class_3 latch class 3
_latch_class_4 latch class 4
_latch_class_5 latch class 5
_latch_class_6 latch class 6
_latch_class_7 latch class 7
_latch_classes latch classes override
_latch_miss_stat_sid 0 Sid of process for which to collect latch stats
_latch_recovery_alignment 65534 align latch recovery structures
_ldr_io_size 262144 size of write IOs used during a load operation
_left_nested_loops_random TRUE enable random distribution method for left of nestedloops
_lgwr_async_broadcasts TRUE LGWR Asynchronous Broadcasts enabling boolean flag
_lgwr_delay_write FALSE LGWR write delay for debugging
_lgwr_io_slaves 0 LGWR I/O slaves
_lgwr_max_ns_wt 1 Maximum wait time for lgwr to allow NetServer to progress
_lgwr_ns_nl_max 1000 Variable to simulate network latency or buffer threshold
_lgwr_ns_nl_min 500 Variable to simulate network latency or buffer threshold
_lgwr_ns_sim_err 0 Variable to simulate errors lgwrns
_lgwr_ta_sim_err 0 Variable to simulate errors lgwr true async
_library_cache_advice TRUE whether KGL advice should be turned on
_lightweight_hdrs TRUE Lightweight headers for redo
_like_with_bind_as_equality FALSE treat LIKE predicate with bind as an equality predicate
_lm_activate_lms_threshold 100 threshold value to activate an additional lms
_lm_asm_enq_hashing TRUE if TRUE makes ASM use enqueue master hashing for fusion locks
_lm_better_ddvictim TRUE GES better deadlock victim
_lm_cache_lvl0_cleanup 0 how often to cleanup level 0 cache res (in sec)
_lm_cache_res_cleanup 25 percentage of cached resources should be cleanup
_lm_cache_res_type TMHWDI cache resource: string of lock types(s)
_lm_checksum_batch_msg 0 GES checksum batch messages
_lm_contiguous_res_count 128 number of contiguous blocks that will hash to the same HV bucket
_lm_dd_interval 10 dd time interval in seconds
_lm_dd_max_search_time 180 max dd search time per token
_lm_dd_scan_interval 5 dd scan interval in seconds
_lm_dd_search_cnt 3 number of dd search per token get
_lm_drm_max_requests 100 dynamic remastering maximum affinity requests processed together
_lm_drm_window 0 dynamic remastering bucket window size
_lm_drm_xlatch 0 dynamic remastering forced exclusive latches
_lm_dynamic_lms FALSE dynamic lms invocation
_lm_dynamic_load TRUE dynamic load adjustment
_lm_enq_lock_freelist Number of ges enqueue element freelist
_lm_enq_rcfg TRUE if TRUE enables enqueue reconfiguration
_lm_enqueue_freelist 3 Number of enqueue freelist
_lm_file_affinity mapping between file id and master instance number
_lm_global_posts TRUE if TRUE deliver global posts to remote nodes
_lm_idle_connection_check TRUE GES idle connection check
_lm_idle_connection_check_interval 10 GES idle connection check interval time
_lm_idle_connection_kill FALSE GES idle connection kill
_lm_lmd_waittime 8 default wait time for lmd in centiseconds
_lm_lmon_nowait_latch TRUE if TRUE makes lmon get nowait latches with timeout loop
_lm_lms 0 number of background gcs server processes to start
_lm_lms_waittime 8 default wait time for lms in centiseconds
_lm_locks 12000 number of enqueues configured for cluster database
_lm_master_weight 1 master resource weight for this instance
_lm_max_lms 0 max. number of background global cache server processes
_lm_msg_batch_size 0 GES batch message size
_lm_msg_cleanup_interval 3000 GES message buffer cleanup interval time
_lm_node_join_opt FALSE cluster database node join optimization in reconfig
_lm_non_fault_tolerant FALSE disable cluster database fault-tolerance mode
_lm_num_pt_buckets 8192 number of buckets in the object affinity hash table
_lm_num_pt_latches 128 number of latches in the object affinity hash table
_lm_postevent_buffer_size 256 postevent buffer size
_lm_proc_freeze_timeout 300 reconfiguration: process freeze timeout
_lm_process_batching TRUE GES implicit process batching for IPC messages
_lm_procs 320 number of client processes configured for cluster database
_lm_psrcfg FALSE enable pseudo reconfiguration
_lm_rcfg_timeout 1260 Reconfiguration timeout
_lm_rcvr_hang_allow_time 200 receiver hang allow time in seconds
_lm_rcvr_hang_check_frequency 60 receiver hang check frequency in seconds
_lm_rcvr_hang_kill FALSE to kill receiver hang
_lm_res_hash_bucket 0 number of resource hash buckets
_lm_res_part 128 number of resource partition configured for gcs
_lm_ress 6000 number of resources configured for cluster database
_lm_send_mode auto GES send mode
_lm_send_queue_batching TRUE GES send queue message batching
_lm_send_queue_length 5000 GES send queue maximum length
_lm_sendproxy_reserve 25 GES percentage of send proxy reserve of send tickets
_lm_share_lock_opt FALSE if TRUE enables share lock optimization
_lm_sq_batch_factor 2 GES send queue minimum batching factor
_lm_sq_batch_type auto GES send queue batching mechanism
_lm_sq_batch_waittick 3 GES send queue batching waittime in tick
_lm_sync_timeout 420 Synchronization timeout for DLM reconfiguration steps
_lm_ticket_active_sendback Flow control ticket active sendback threshold
_lm_tickets 1000 GES messaging tickets
_lm_tx_delta 16 TX lock localization delta
_lm_validate_resource_type FALSE if TRUE enables resource name validation
_lm_xids 352 number of transaction IDs configured for cluster database
_lmn_compression FALSE suppl logging for compression enabled
_load_without_compile NONE Load PL/SQL or Database objects without compilation
_local_communication_costing_enabled TRUE enable local communication costing when TRUE
_local_communication_ratio 50 set the ratio between global and local communication (0..100)
_local_hang_analysis_interval_secs 3 the interval at which local hang analysis is run
_lock_sga_areas 0 Lock specified areas of the SGA in physical memory
_log_archive_avoid_memcpy TRUE log archive avoid memcpy
_log_archive_buffers 10 Number of buffers to allocate for archiving
_log_archive_callout archival callout
_log_archive_compress_enable FALSE Bypass database rules for enabling archivelog compression
_log_archive_network_redo_size 10 Log archive network redo buffer size used by ARCH
_log_archive_prot_auto_demote FALSE log archive protection auto demotion
_log_archive_security_enabled TRUE log archive security enabled
_log_archive_strong_auth TRUE log archive security strong auth
_log_blocks_during_backup TRUE log block images when changed during backup
_log_buffers_corrupt FALSE corrupt redo buffers before write
_log_buffers_debug FALSE debug redo buffers (slows things down)
_log_checkpoint_recovery_check 0 # redo blocks to verify after checkpoint
_log_committime_block_cleanout FALSE Log commit-time block cleanout
_log_deletion_policy mandatory archivelog deletion policy for mandatory/all destination
_log_event_queues 0 number of the log writer event queues
_log_io_size 0 automatically initiate log write if this many redo blocks in buffer
_log_parallelism_dynamic TRUE Enable dynamic strands
_log_parallelism_max 1 Maximum number of log buffer strands
_log_private_mul 5 Private strand multiplier for log space preallocation
_log_private_parallelism FALSE Number of private log buffer strands for zero-copy redo
_log_private_parallelism_mul 10 Active sessions multiplier to deduce number of private strands
_log_read_buffers 4 Number of log read buffers for media recovery
_log_simultaneous_copies 2 number of simultaneous copies into redo buffer(# of copy latches)
_log_space_errors TRUE should we report space errors to alert log
_log_switch_timeout 0 Maximum number of seconds redos in the current log could span
_logout_storm_rate 0 number of processes that can logout in a second
_logout_storm_retrycnt 600 maximum retry count for logouts
_logout_storm_timeout 5 timeout in centi-seconds for time to wait between retries
_longops_enabled TRUE longops stats enabled
_low_server_threshold 0 low server thresholds
_ltc_trace 0 tracing level for load table conventional
_master_direct_sends 31 direct sends for messages from master (DFS)
_mav_refresh_consistent_read TRUE refresh materialized views using consistent read snapshot
_mav_refresh_double_count_prevented FALSE materialized view MAV refreshes avoid double counting
_mav_refresh_opt 0 optimizations during refresh of materialized views
_mav_refresh_unionall_tables 3 # tables for union all expansion during materialized view refresh
_max_arch_lns_wait 120 Maximum wait by ARCH to allow NetServer to complete archival
_max_exponential_sleep 0 max sleep during exponential backoff
_max_io_size 1048576 Maximum I/O size in bytes for sequential file accesses
_max_large_io 0 IORM:max number of large I/O’s to issue
_max_lns_shutdown_archival_time 30 Maximum time spent by LNS to archive last log during shutdown
_max_protocol_support 10000 Max occurrence protocols supported in a process
_max_shrink_obj_stats 0 number of segments for which shrink stats will be maintained
_max_sleep_holding_latch 4 max time to sleep while holding a latch
_max_small_io 0 IORM:max number of small I/O’s to issue
_max_spacebg_slaves 10 maximum space management background slaves
_max_spacebg_tasks 1000 maximum space management background tasks
_max_temp_overhead 0 max tempspc overhead
_media_recovery_read_batch 128 media recovery block read batch
_mem_annotation_pr_lev 0 private memory annotation collection level
_mem_annotation_scale 1 memory annotation pre-allocation scaling
_mem_annotation_sh_lev 0 shared memory annotation collection level
_mem_annotation_store FALSE memory annotation in-memory store
_mem_std_extent_size 4096 standard extent size for fixed-size-extent heaps
_memory_broker_log_stat_entries 5 memory broker num stat entries
_memory_broker_marginal_utility_bc 12 Marginal Utility threshold pct for bc
_memory_broker_marginal_utility_sp 7 Marginal Utility threshold pct for sp
_memory_broker_shrink_heaps 15 memory broker allow policy to shrink shared pool
_memory_broker_shrink_java_heaps 900 memory broker allow policy to shrink java pool
_memory_broker_shrink_streams_pool 900 memory broker allow policy to shrink streams pool
_memory_broker_shrink_timeout 60000000 memory broker policy to timeout shrink shared/java pool
_memory_broker_stat_interval 30 memory broker statistics gathering interval for auto sga
_memory_management_tracing 0 trace memory management activity
_memory_nocancel_defsgareq FALSE do not cancel deferred sga reqs with auto-memory
_memory_sanity_check 0 partial granule sanity check
_messages 300 message queue resources – dependent on # processes & # buffers
_midtier_affinity_clusterwait_threshold 100 cluster wait threshold to enter affinity
_midtier_affinity_goodness_threshold 2000 goodness gradient threshold to dissolve affinity
_midtier_affinity_timeout 30000 default timeout for midtier affinity processing
_minfree_plus 0 max percentage of block space + minfree before we mark block full
_minimal_stats_aggregation TRUE prohibit stats aggregation at compile/partition maintenance time
_minimum_blocks_to_shrink 0 minimum number freeable blocks for shrink to be present
_minimum_db_flashback_retention 60 Minimum flashback retention
_minimum_extents_to_shrink 1 minimum number freeable extents for shrink to be present
_minimum_giga_scn 0 Minimum SCN to start with in 2^30 units
_mirror_redo_buffers FALSE Save buffers for debugging redo corruptions
_mmv_query_rewrite_enabled TRUE allow rewrites with multiple MVs and/or base tables
_multi_instance_pmr TRUE force multi instance or single instance parallel recovery
_multi_join_key_table_lookup TRUE TRUE iff multi-join-key table lookup prefetch is enabled
_multiple_instance_recovery FALSE use multiple instances for media recovery
_mv_refresh_ana 0 what percent to analyze after complete/PCT refresh
_mv_refresh_costing rule refresh decision based on cost or on rules
_mv_refresh_delta_fraction 10 delta mv as fractional percentage of size of mv
_mv_refresh_eut TRUE refresh materialized views using EUT(partition)-based algorithm
_mv_refresh_force_parallel_query 0 force materialized view refreshes to use parallel query
_mv_refresh_new_setup_disabled FALSE materialized view MV refresh new setup disabling
_mv_refresh_rebuild_percentage 10 minimum percentage change required in MV to force an indexrebuild
_mv_refresh_selections TRUE create materialized views with selections and fast refresh
_mv_refresh_use_stats FALSE pass cardinality hints to refresh queries
_mv_refsched_timeincr 300000 proportionality constant for dop vs. time in MV refresh
_mv_rolling_inv FALSE create/alter mv uses rolling cursor invalidation instead of immediate
_mwin_schedule TRUE Enable/disable Maintenance Window Schedules
_nchar_imp_cnv TRUE NLS allow Implicit Conversion between CHAR and NCHAR
_nchar_imp_conv TRUE should implicit conversion bewteen clob and nclob be allowed
_ncmb_readahead_enabled 0 enable multi-block readahead for an index scan
_ncmb_readahead_tracing 0 turn on multi-block readahead tracing
_ncomp_shared_objects_dir native compilation shared objects dir
_nested_loop_fudge 100 nested loop fudge
_nested_mav_fast_oncommit_enabled TRUE nested MAV refresh fast on commit allowed
_new_initial_join_orders TRUE enable initial join orders based on new ordering heuristics
_new_sort_cost_estimate TRUE enables the use of new cost estimate for sort
_newsort_enabled TRUE controls whether new sorts can be used as system sort
_newsort_ordered_pct 63 controls when new sort avoids sorting ordered input
_newsort_type 0 specifies options for the new sort algorithm
_nlj_batching_enabled 1 enable batching of the RHS IO in NLJ
_nlj_batching_misses_enabled 1 enable exceptions for buffer cache misses
_no_objects FALSE no object features are used
_no_or_expansion FALSE OR expansion during optimization disabled
_no_recovery_through_resetlogs FALSE no recovery through this resetlogs operation
_notify_crs FALSE notify cluster ready services of startup and shutdown
_ns_max_flush_wt 1 Flush wait time for NetServer to flush oustanding writes
_ns_max_send_delay 15 Data Loss Time Bound for NetServer
_num_longop_child_latches 1 number of child latches for long op array
_number_cached_attributes 10 maximum number of cached attributes per instance
_object_reuse_bast 2 if 1 or higher, handle object reuse
_object_statistics TRUE enable the object level statistics collection
_object_stats_max_entries 3072 Maximum number of entries to be tracked per stat
_offline_rollback_segments offline undo segment list
_ogms_home GMS home directory
_olap_aggregate_buffer_size 1048576 OLAP Aggregate max buffer size
_olap_aggregate_flags 0 OLAP Aggregate debug flags
_olap_aggregate_function_cache_enabled TRUE OLAP Aggregate function cache enabler
_olap_aggregate_function_merge_threshold 529 OLAP Aggregate function merge threshold
_olap_aggregate_max_thread_tuples 5000 OLAP Aggregate max thread tuples creation
_olap_aggregate_min_buffer_size 1024 OLAP Aggregate min buffer size
_olap_aggregate_min_thread_status 64 OLAP Aggregate minimum cardinality of dimensions for thread
_olap_aggregate_multipath_hier FALSE OLAP Aggregate Multi-path Hierarhies enabled
_olap_aggregate_statlen_thresh 1024 OLAP Aggregate status array usage threshold
_olap_aggregate_store_probability 100 OLAP Aggregate function storeback probability
_olap_aggregate_work_per_thread 1024 OLAP Aggregate max work parents
_olap_aggregate_worklist_max 5000 OLAP Aggregate max worklists generated at once
_olap_allocate_errorlog_format %8p %8y %8z %e (%n) OLAP Allocate Errorlog Format
_olap_allocate_errorlog_header Dim Source Basis %-8d %-8s %-8b Description ——– ——– ——– ———– OLAP Allocate Errorlog Header format
_olap_analyze_max 10000 OLAP DML ANALYZE command max cells to analyze
_olap_continuous_trace_file FALSE Specify TRUE to enable continuous OLAP tracing – otherwise only exceptional events will be logged
_olap_dbgoutfile_echo_to_eventlog FALSE OLAP DbgOutfile copy output to event log (tracefile)
_olap_dimension_corehash_class 1 OLAP Dimension In-Core Hash Table Class
_olap_dimension_corehash_large 50000 OLAP Dimension In-Core Hash Table Large Threshold
_olap_dimension_corehash_pressure 90 OLAP Dimension In-Core Hash Table Pressure Threshold
_olap_dimension_corehash_size 30 OLAP Dimension In-Core Hash Table Maximum Memory Use
_olap_dimension_corehash_small 1000 OLAP Dimension In-Core Hash Table Small Threshold
_olap_eif_export_lob_size 2147483647 OLAP EIF Export BLOB size
_olap_lmgen_dim_size 100 Limitmap generator dimension column size
_olap_lmgen_meas_size 1000 Limitmap generator measure column size
_olap_object_hash_class 2 OLAP Object Hash Table Class
_olap_page_pool_expand_rate 20 OLAP Page Pool Expand Rate
_olap_page_pool_hi 50 OLAP Page Pool High Watermark
_olap_page_pool_hit_target 100 OLAP Page Pool Hit Target
_olap_page_pool_low 262144 OLAP Page Pool Low Watermark
_olap_page_pool_pressure 90 OLAP Page Pool Pressure Threshold
_olap_page_pool_shrink_rate 50 OLAP Page Pool Shrink Rate
_olap_parallel_update_small_group 400 OLAP parallel update pagespace by group
_olap_parallel_update_small_threshold 1000 OLAP parallel update threshold for number of small pagespaces
_olap_parallel_update_threshold 1000 OLAP parallel update threshold in pages
_olap_poutlog_echo_to_eventlog FALSE OLAP POutLog copy output to event log (tracefile)
_olap_sesscache_enabled TRUE OLAP Session Cache knob
_olap_sort_buffer_size 262144 OLAP Sort Buffer Size
_olap_statbool_corebits 20000000 OLAP Status Boolean max incore bits
_olap_statbool_threshold 8100 OLAP Status Boolean CBM threshold
_olap_table_function_statistics FALSE Specify TRUE to output OLAP table function timed statistics trace
_olap_wrap_errors FALSE Wrap error messages to OLAP outfile
_olapi_history_retention FALSE enable olapi history retention
_olapi_iface_object_history 1000 enable olapi interface object history collection
_olapi_iface_object_history_retention FALSE enable olapi interface object history retention
_olapi_iface_operation_history_retention FALSE enable olapi interface operation history retention
_olapi_interface_operation_history 1000 enable olapi interface operation history collection
_olapi_memory_operation_history 1000 enable olapi memory alloc/free history collection
_olapi_memory_operation_history_pause_at_seqno 0 enable olapi memory alloc/free history collection pausing
_olapi_memory_operation_history_retention FALSE enable olapi memory operation history retention
_olapi_session_history 300 enable olapi session history collection
_olapi_session_history_retention FALSE enable olapi session history retention
_old_connect_by_enabled FALSE enable/disable old connect by
_ols_cleanup_task TRUE Clean up unnecessary entries in OLS sessinfo table
_oltp_compression TRUE oltp compression enabled
_oltp_compression_gain 10 oltp compression gain
_omf enabled enable/disable OMF
_oneside_colstat_for_equijoins TRUE sanity check on default selectivity for like/range predicate
_online_patch_disable_stack_check FALSE disable check for function on stack for online patches
_optim_adjust_for_part_skews TRUE adjust stats for skews across partitions
_optim_dict_stats_at_db_cr_upg TRUE enable/disable dictionary stats gathering at db create/upgrade
_optim_enhance_nnull_detection TRUE TRUE to enable index [fast] full scan more often
_optim_new_default_join_sel TRUE improves the way default equijoin selectivity are computed
_optim_peek_user_binds TRUE enable peeking of user binds
_optimizer_adaptive_cursor_sharing TRUE optimizer adaptive cursor sharing
_optimizer_adjust_for_nulls TRUE adjust selectivity for null values
_optimizer_autostats_job TRUE enable/disable auto stats collection job
_optimizer_aw_join_push_enabled TRUE Enables AW Join Push optimization
_optimizer_aw_stats_enabled TRUE Enables statistcs on AW olap_table table function
_optimizer_better_inlist_costing ALL enable improved costing of index access using in-list(s)
_optimizer_block_size 8192 standard block size used by optimizer
_optimizer_cache_stats FALSE cost with cache statistics
_optimizer_cartesian_enabled TRUE optimizer cartesian join enabled
_optimizer_cbqt_factor 50 cost factor for cost-based query transformation
_optimizer_cbqt_no_size_restriction TRUE disable cost based transformation query size restriction
_optimizer_ceil_cost TRUE CEIL cost in CBO
_optimizer_choose_permutation 0 force the optimizer to use the specified permutation
_optimizer_complex_pred_selectivity TRUE enable selectivity estimation for builtin functions
_optimizer_compute_index_stats TRUE force index stats collection on index creation/rebuild
_optimizer_connect_by_combine_sw TRUE combine no filtering connect by and start with
_optimizer_connect_by_cost_based TRUE use cost-based transformation for connect by
_optimizer_correct_sq_selectivity TRUE force correct computation of subquery selectivity
_optimizer_cost_based_transformation LINEAR enables cost-based query transformation
_optimizer_cost_filter_pred FALSE enables costing of filter predicates in IO cost model
_optimizer_cost_hjsmj_multimatch TRUE add cost of generating result set when #rows per key > 1
_optimizer_cost_model CHOOSE optimizer cost model
_optimizer_degree 0 force the optimizer to use the same degree of parallelism
_optimizer_dim_subq_join_sel TRUE use join selectivity in choosing star transformation dimensions
_optimizer_disable_strans_sanity_checks 0 disable star transformation sanity checks
_optimizer_distinct_elimination TRUE Eliminates redundant SELECT DISTNCT’s
_optimizer_dyn_smp_blks 32 number of blocks for optimizer dynamic sampling
_optimizer_enable_density_improvements TRUE use improved density computation for selectivity estimation
_optimizer_enable_extended_stats TRUE use extended statistics for selectivity estimation
_optimizer_enhanced_filter_push TRUE push filters before trying cost-based query transformation
_optimizer_extend_jppd_view_types TRUE join pred pushdown on group-by, distinct, semi-/anti-joined view
_optimizer_extended_cursor_sharing UDO optimizer extended cursor sharing
_optimizer_extended_cursor_sharing_rel SIMPLE optimizer extended cursor sharing for relational operators
_optimizer_extended_stats_usage_control 240 controls the optimizer usage of extended stats
_optimizer_filter_pred_pullup TRUE use cost-based flter predicate pull up transformation
_optimizer_fkr_index_cost_bias 10 Optimizer index bias over FTS/IFFS under first K rows mode
_optimizer_free_transformation_heap TRUE free transformation subheap after each transformation
_optimizer_group_by_placement TRUE consider group-by placement optimization
_optimizer_ignore_hints FALSE enables the embedded hints to be ignored
_optimizer_improve_selectivity TRUE improve table and partial overlap join selectivity computation
_optimizer_invalidation_period 18000 time window for invalidation of cursors of analyzed objects
_optimizer_join_elimination_enabled TRUE optimizer join elimination enabled
_optimizer_join_order_control 3 controls the optimizer join order search algorithm
_optimizer_join_sel_sanity_check TRUE enable/disable sanity check for multi-column join selectivity
_optimizer_max_permutations 2000 optimizer maximum join permutations per query block
_optimizer_min_cache_blocks 10 set minimum cached blocks
_optimizer_mjc_enabled TRUE enable merge join cartesian
_optimizer_mode_force TRUE force setting of optimizer mode for user recursive SQL also
_optimizer_multi_level_push_pred TRUE consider join-predicate pushdown that requires multi-level pushdown to base table
_optimizer_multiple_cenv generate and run plans using several compilation environments
_optimizer_native_full_outer_join FORCE execute full outer join using native implementaion
_optimizer_nested_rollup_for_gset 100 number of groups above which we use nested rollup exec for gset
_optimizer_new_join_card_computation TRUE compute join cardinality using non-rounded input values
_optimizer_null_aware_antijoin TRUE null-aware antijoin parameter
_optimizer_or_expansion DEPTH control or expansion approach used
_optimizer_or_expansion_subheap TRUE Use subheap for optimizer or-expansion
_optimizer_order_by_elimination_enabled TRUE Eliminates order bys from views before query transformation
_optimizer_outer_to_anti_enabled TRUE Enable transformation of outer-join to anti-join if possible
_optimizer_percent_parallel 101 optimizer percent parallel
_optimizer_push_down_distinct 0 push down distinct from query block to table
_optimizer_push_pred_cost_based TRUE use cost-based query transformation for push pred optimization
_optimizer_random_plan 0 optimizer seed value for random plans
_optimizer_reuse_cost_annotations TRUE reuse cost annotations during cost-based query transformation
_optimizer_rownum_bind_default 10 Default value to use for rownum bind
_optimizer_rownum_pred_based_fkr TRUE enable the use of first K rows due to rownum predicate
_optimizer_save_stats TRUE enable/disable saving old versions of optimizer stats
_optimizer_search_limit 5 optimizer search limit
_optimizer_self_induced_cache_cost FALSE account for self-induced caching
_optimizer_skip_scan_enabled TRUE enable/disable index skip scan
_optimizer_skip_scan_guess FALSE consider index skip scan for predicates with guessed selectivity
_optimizer_sortmerge_join_enabled TRUE enable/disable sort-merge join method
_optimizer_sortmerge_join_inequality TRUE enable/disable sort-merge join using inequality predicates
_optimizer_squ_bottomup TRUE enables unnesting of subquery in a bottom-up manner
_optimizer_star_tran_in_with_clause TRUE enable/disable star transformation in with clause queries
_optimizer_star_trans_min_cost 0 optimizer star transformation minimum cost
_optimizer_star_trans_min_ratio 0 optimizer star transformation minimum ratio
_optimizer_starplan_enabled TRUE optimizer star plan enabled
_optimizer_system_stats_usage TRUE system statistics usage
_optimizer_trace none optimizer trace parameter
_optimizer_transitivity_retain TRUE retain equi-join pred upon transitive equality pred generation
_optimizer_undo_changes FALSE undo changes to query optimizer
_optimizer_undo_cost_change optimizer undo cost change
_optimizer_use_subheap TRUE Enables physical optimizer subheap
_or_expand_nvl_predicate TRUE enable OR expanded plan for NVL/DECODE predicate
_oradbg_pathname path of oradbg script
_oradebug_force FALSE force target processes to execute oradebug commands?
_ordered_nested_loop TRUE enable ordered nested loop costing
_ordered_semijoin TRUE enable ordered semi-join subquery
_orph_cln_interval 1200 qmon periodic interval for removed subscriber messages cleanup
_os_sched_high_priority 1 OS high priority level
_other_wait_event_exclusion exclude event names from _other_wait_threshold calculations
_other_wait_threshold 0 threshold wait percentage for event wait class Other
_outline_bitmap_tree TRUE BITMAP_TREE hint enabled in outline
_parallel_adaptive_max_users 2 maximum number of users running with default DOP
_parallel_broadcast_enabled TRUE enable broadcasting of small inputs to hash and sort merge joins
_parallel_default_max_instances 1 default maximum number of instances for parallel query
_parallel_execution_message_align FALSE Alignment of PX buffers to OS page boundary
_parallel_fake_class_pct 0 fake db-scheduler percent used for testing
_parallel_fixwrite_bucket 1000 Number of buckets for each round of fix write
_parallel_load_bal_unit 0 number of threads to allocate per instance
_parallel_load_balancing TRUE parallel execution load balanced slave allocation
_parallel_min_message_pool 206592 minimum size of shared pool memory to reserve for pq servers
_parallel_policy MANUAL policy used to compute the degree of parallelism (MANUAL/LIMITED/AUTO)
_parallel_recovery_stopat 32767 stop at -position- to step through SMON
_parallel_replay_msg_limit 4000 Number of messages for each round of parallel replay
_parallel_server_idle_time 30000 idle time before parallel query server dies (in 1/100 sec)
_parallel_server_sleep_time 10 sleep time between dequeue timeouts (in 1/100ths)
_parallel_slave_acquisition_wait 1 time(in seconds) to wait before retrying slave acquisition
_parallel_time_threshold 10 threshold above which a plan is a candidate for parallelization (in seconds)
_parallel_time_unit 10 unit of work used to derive the degree of parallelism (in seconds)
_parallel_txn_global FALSE enable parallel_txn hint with updates and deletes
_parallelism_cost_fudge_factor 350 set the parallelism cost fudge factor
_parameter_table_block_size 2048 parameter table block size
_partial_pwise_join_enabled TRUE enable partial partition-wise join when TRUE
_partition_view_enabled TRUE enable/disable partitioned views
_passwordfile_enqueue_timeout 900 password file enqueue timeout in seconds
_pct_refresh_double_count_prevented TRUE materialized view PCT refreshes avoid double counting
_pdml_gim_sampling 5000 control separation of global index maintenance for PDML
_pdml_gim_staggered FALSE slaves start on different index when doing index maint
_pdml_slaves_diff_part TRUE slaves start on different partition when doing index maint
_percent_flashback_buf_partial_full 50 Percent of flashback buffer filled to be considered partial full
_pga_large_extent_size 1048576 PGA large extent size
_pga_max_size 209715200 Maximum size of the PGA memory for one process
_ping_level 3 fusion ping level
_pivot_implementation_method CHOOSE pivot implementation method
_pkt_enable FALSE enable progressive kill test
_pkt_pmon_interval 50 PMON process clean-up interval (cs)
_pkt_start FALSE start progressive kill test instrumention
_plan_outline_data TRUE explain plan outline data enabled
_plan_verify_improvement_margin 150 Performance improvement criterion for evolving plan baselines
_plan_verify_local_time_limit 0 Local time limit to use for an individual plan verification
_plsql_anon_block_code_type INTERPRETED PL/SQL anonymous block code-type
_plsql_cache_enable TRUE PL/SQL Function Cache Enabled
_plsql_dump_buffer_events conditions upon which the PL/SQL circular buffer is dumped
_plsql_minimum_cache_hit_percent 20 plsql minimum cache hit percentage required to keep caching active
_plsql_nvl_optimize FALSE PL/SQL NVL optimize
_pmon_load_constants 300,192,64,3,10,10,0,0 server load balancing constants (S,P,D,I,L,C,M)
_pre_rewrite_push_pred TRUE push predicates into views before rewrite
_precompute_gid_values TRUE precompute gid values and copy them before returning a row
_pred_move_around TRUE enables predicate move-around
_predicate_elimination_enabled TRUE allow predicate elimination if set to TRUE
_prescomm FALSE presume commit of IMU transactions
_print_refresh_schedule false enable dbms_output of materialized view refresh schedule
_private_memory_address Start address of large extent memory segment
_project_view_columns TRUE enable projecting out unreferenced columns of a view
_projection_pushdown TRUE projection pushdown
_projection_pushdown_debug 0 level for projection pushdown debugging
_prop_old_enabled FALSE Shift to pre 11g propagation behaviour
_protect_frame_heaps FALSE Protect cursor frame heaps
_push_join_predicate TRUE enable pushing join predicate inside a view
_push_join_union_view TRUE enable pushing join predicate inside a union all view
_push_join_union_view2 TRUE enable pushing join predicate inside a union view
_px_async_getgranule FALSE asynchronous get granule in the slave
_px_bind_peek_sharing TRUE enables sharing of px cursors that were built using bind peeking
_px_broadcast_fudge_factor 100 set the tq broadcasting fudge factor percentage
_px_buffer_ttl 30 ttl for px mesg buffers in seconds
_px_compilation_debug 0 debug level for parallel compilation
_px_compilation_trace 0 tracing level for parallel compilation
_px_dump_12805_source TRUE enables or disables tracing of 12805 signal source
_px_dynamic_opt TRUE turn off/on restartable qerpx dynamic optimization
_px_dynamic_sample_size 50 num of samples for restartable qerpx dynamic optimization
_px_execution_services_enabled TRUE enable service-based constraint of px slave allocation
_px_granule_size 100000 default size of a rowid range granule (in KB)
_px_index_sampling 200 parallel query sampling for index create (100000 = 100%)
_px_io_process_bandwidth 200 IO process bandwidth in MB/sec for computing DOP
_px_io_system_bandwidth 0 total IO system bandwidth in MB/sec for computing DOP
_px_kxib_tracing 0 turn on kxib tracing
_px_load_publish_interval 200 interval at which LMON will check whether to publish PX load
_px_loc_msg_cost 1000 CPU cost to send a PX message via shared memory
_px_max_granules_per_slave 100 maximum number of rowid range granules to generate per slave
_px_min_granules_per_slave 13 minimum number of rowid range granules to generate per slave
_px_minus_intersect TRUE enables pq for minus/interect operators
_px_net_msg_cost 10000 CPU cost to send a PX message over the internconnect
_px_no_granule_sort FALSE prevent parallel partition granules to be sorted on size
_px_no_stealing FALSE prevent parallel granule stealing in shared nothing environment
_px_nss_planb TRUE enables or disables NSS Plan B reparse with outline
_px_proc_constrain TRUE reduce parallel_max_servers if greater than (processes – fudge)
_px_pwg_enabled TRUE parallel partition wise group by enabled
_px_rownum_pd TRUE turn off/on parallel rownum pushdown optimization
_px_send_timeout 300 IPC message send timeout value in seconds
_px_slaves_share_cursors 0 slaves share cursors with QC
_px_trace none px trace parameter
_px_ual_serial_input TRUE enables new pq for UNION operators
_px_xtgranule_size 10000 default size of a external table granule (in KB)
_qa_control 0 Oracle internal parameter to control QA
_qa_lrg_type 0 Oracle internal parameter to specify QA lrg type
_query_cost_rewrite TRUE perform the cost based rewrite with materialized views
_query_execution_cache_max_size 65536 max size of query execution cache
_query_mmvrewrite_maxcmaps 20 query mmv rewrite maximum number of cmaps per dmap in query disjunct
_query_mmvrewrite_maxdmaps 10 query mmv rewrite maximum number of dmaps per query disjunct
_query_mmvrewrite_maxinlists 5 query mmv rewrite maximum number of in-lists per disjunct
_query_mmvrewrite_maxintervals 5 query mmv rewrite maximum number of intervals per disjunct
_query_mmvrewrite_maxmergedcmaps 50 query mmv rewrite maximum number of merged cmaps
_query_mmvrewrite_maxpreds 10 query mmv rewrite maximum number of predicates per disjunct
_query_mmvrewrite_maxqryinlistvals 500 query mmv rewrite maximum number of query in-list values
_query_mmvrewrite_maxregperm 512 query mmv rewrite maximum number of region permutations
_query_rewrite_1 TRUE perform query rewrite before&after or only before view merging
_query_rewrite_2 TRUE perform query rewrite before&after or only after view merging
_query_rewrite_drj TRUE mv rewrite and drop redundant joins
_query_rewrite_expression TRUE rewrite with cannonical form for expressions
_query_rewrite_fpc TRUE mv rewrite fresh partition containment
_query_rewrite_fudge 90 cost based query rewrite with MVs fudge factor
_query_rewrite_jgmigrate TRUE mv rewrite with jg migration
_query_rewrite_maxdisjunct 257 query rewrite max disjuncts
_query_rewrite_or_error FALSE allow query rewrite, if referenced tables are not dataless
_query_rewrite_setopgrw_enable TRUE perform general rewrite using set operator summaries
_query_rewrite_vop_cleanup TRUE prune frocol chain before rewrite after view-merging
_rcfg_parallel_fixwrite TRUE if TRUE enables parallel fixwrite at reconfiguration
_rcfg_parallel_replay TRUE if TRUE enables parallel replay and cleanup at reconfiguration
_rcfg_parallel_verify TRUE if TRUE enables parallel verify at reconfiguration
_rdbms_compatibility 10.1 default RDBMS compatibility level
_rdbms_internal_fplib_enabled FALSE enable SAGE FPLIB filtering within rdbms
_rdbms_internal_fplib_raise_errors FALSE enable reraising of any exceptions in SAGE FPLIB
_readable_standby_mode SLFLUSH readable standby mode
_readable_standby_sync_timeout 10 readable standby query scn sync timeout
_real_time_apply_sim 0 Simulation value with real time apply
_realfree_heap_max_size 32768 minimum max total heap size, in Kbytes
_realfree_heap_mode 0 mode flags for real-free heap
_realfree_heap_pagesize_hint 65536 hint for real-free page size in bytes
_recoverable_recovery_batch_percent 50 Recoverable recovery batch size (percentage of buffer cache)
_recovery_asserts FALSE if TRUE, enable expensive integrity checks
_recovery_percentage 50 recovery buffer cache percentage
_recovery_verify_writes FALSE enable thread recovery write verify
_recursive_imu_transactions FALSE recursive transactions may be IMU
_redo_compatibility_check FALSE general and redo/undo compatibility sanity check
_redo_read_from_memory TRUE Enable reading redo from memory
_redo_transport_compress_all FALSE Is ASYNC LNS compression allowed?
_release_insert_threshold 5 maximum number of unusable blocks to unlink from freelist
_reliable_block_sends FALSE if TRUE, block sends across interconnect are reliable
_remove_aggr_subquery TRUE enables removal of subsumed aggregated subquery
_replace_virtual_columns TRUE replace expressions with virtual columns
_resource_manager_always_off FALSE disable the resource manager always
_resource_manager_always_on TRUE enable the resource manager always
_restore_spfile restore spfile to this location
_result_cache_auto_execution_threshold 1 result cache auto execution threshold
_result_cache_auto_size_threshold 100 result cache auto max size allowed
_result_cache_auto_time_distance 300 result cache auto time distance
_result_cache_auto_time_threshold 1000 result cache auto time threshold
_result_cache_block_size 1024 result cache block size
_result_cache_timeout 60 maximum time (sec) a session waits for a result
_reuse_index_loop 5 number of blocks being examine for index block reuse
_right_outer_hash_enable TRUE Right Outer/Semi/Anti Hash Enabled
_rman_io_priority 3 priority at which rman backup i/o’s are done
_rman_restore_through_link FALSE RMAN restore through link
_rollback_segment_count 0 number of undo segments
_rollback_segment_initial 1 starting undo segment number
_rollback_stopat 0 stop at -position to step rollback
_row_cache_cursors 20 number of cached cursors for row cache management
_row_cr TRUE enable row cr for all sql
_row_locking always row-locking
_row_shipping_explain FALSE enable row shipping explain plan support
_row_shipping_threshold 80 row shipping column selection threshold
_rowsource_execution_statistics FALSE if TRUE, Oracle will collect rowsource statistics
_rowsource_profiling_statistics TRUE if TRUE, Oracle will capture active row sources in v$active_session_history
_rowsource_statistics_sampfreq 128 frequency of rowsource statistic sampling (must be a power of 2)
_rowsrc_trace_level 0 Row source tree tracing level
_rtc_infeasible_threshold 10 Redo Transport Compression infeasible threshold
_sage_enabled 1 enable real SAGE functionality
_sage_fcre TRUE Allow optimized file creation path for SAGE
_sample_rows_per_block 4 number of rows per block used for sampling IO optimization
_scatter_gcs_resources FALSE if TRUE, gcs resources are scattered uniformly across sub pools
_scatter_gcs_shadows FALSE if TRUE, gcs shadows are scattered uniformly across sub pools
_scn_wait_interface_max_backoff_time_secs 600 max exponential backoff time for scn wait interface in kta
_scn_wait_interface_max_timeout_secs 2147483647 max timeout for scn wait interface in kta
_sdiag_crash NONE sql diag crash
_sec_enable_test_rpcs FALSE Whether to enable the test RPCs
_second_spare_parameter second spare parameter – integer
_securefile_timers FALSE collect kdlu timers and accumulate per layers
_selectivity_for_srf_enabled FALSE enable/disable selectivity for storage reduction factor
_selfjoin_mv_duplicates TRUE control rewrite self-join algorithm
_selftune_checkpoint_write_pct 3 Percentage of total physical i/os for self-tune ckpt
_selftune_checkpointing_lag 300 Self-tune checkpointing lag the tail of the redo log
_send_ast_to_foreground TRUE if TRUE, send ast message to foreground
_send_close_with_block TRUE if TRUE, send close with block even with direct sends
_send_requests_to_pi TRUE if TRUE, try to send CR requests to PI buffers
_serial_direct_read FALSE enable direct read in serial
_serial_recovery FALSE force serial recovery or parallel recovery
_serializable FALSE serializable
_session_cached_instantiations 60 Number of pl/sql instantiations to cache in a session.
_session_context_size 10000 session app context size
_session_idle_bit_latches 0 one latch per session or a latch per group of sessions
_session_idle_check_interval 60 Resource Manager session idle limit check interval in seconds
_session_kept_cursor_pins 0 Number of cursors pins to keep in a session
_session_wait_history 10 enable session wait history collection
_seventh_spare_parameter seventh spare parameter – string list
_sga_clear_dump FALSE Allow dumping encrypted blocks in clear for debugging
_sga_early_trace 0 sga early trace event
_sga_locking none sga granule locking state
_shared_io_pool_buf_size 1048576 Shared IO pool buffer size
_shared_io_pool_debug_trc 0 trace kcbi debug info to tracefile
_shared_io_pool_size 0 Size of shared IO pool
_shared_io_set_value FALSE shared io pool size set internal value – overwrite zero user size
_shared_iop_max_size 536870912 maximum shared io pool size
_shared_pool_max_size 0 shared pool maximum size when auto SGA enabled
_shared_pool_minsize_on FALSE shared pool minimum size when auto SGA enabled
_shared_pool_reserved_min_alloc 4400 minimum allocation size in bytes for reserved area of shared pool
_shared_pool_reserved_pct 5 percentage memory of the shared pool allocated for the reserved area
_shared_server_load_balance 0 shared server load balance
_shared_server_num_queues 1 number of shared server common queues
_short_stack_timeout_ms 30000 short stack timeout in ms
_shrunk_aggs_disable_threshold 60 percentage of exceptions at which to switch to full length aggs
_shrunk_aggs_enabled TRUE enable use of variable sized buffers for non-distinct aggregates
_side_channel_batch_size 200 number of messages to batch in a side channel message (DFS)
_side_channel_batch_timeout 6 timeout before shipping out the batched side channelmessages in seconds
_side_channel_batch_timeout_ms 500 timeout before shipping out the batched side channelmessages in milliseconds
_simple_view_merging TRUE control simple view merging performed by the optimizer
_simulate_mem_transfer FALSE simulate auto memory sga/pga transfers
_simulator_bucket_mindelta 8192 LRU bucket minimum delta
_simulator_internal_bound 10 simulator internal bound percent
_simulator_lru_rebalance_sizthr 5 LRU list rebalance threshold (size)
_simulator_lru_rebalance_thresh 10240 LRU list rebalance threshold (count)
_simulator_lru_scan_count 8 LRU scan count
_simulator_pin_inval_maxcnt 16 maximum count of invalid chunks on pin list
_simulator_reserved_heap_count 4096 simulator reserved heap count
_simulator_reserved_obj_count 1024 simulator reserved object count
_simulator_sampling_factor 2 sampling factor for the simulator
_simulator_upper_bound_multiple 2 upper bound multiple of pool size
_single_process FALSE run without detached processes
_siop_flashback_scandepth 20 Shared IO pool flashback io completion scan depth
_sixth_spare_parameter sixth spare parameter – string list
_skgxp_reaping 1000 tune skgxp OSD reaping limit
_skgxp_udp_ach_reaping_time 120 time in minutes before idle ach’s are reaped
_skgxp_udp_ack_delay 0 Enables delayed acks
_skgxp_udp_enable_dynamic_credit_mgmt 0 Enables dynamic credit management
_skgxp_udp_hiwat_warn 1000 ach hiwat mark warning interval
_skgxp_udp_interface_detection_time_secs 60 time in seconds between interface detection checks
_skgxp_udp_keep_alive_ping_timer_secs 300 connection idle time in seconds before keep alive is initiated. min: 30 sec max: 1800 sec default: 300 sec
_skgxp_udp_lmp_mtusize 0 MTU size for UDP LMP testing
_skgxp_udp_lmp_on FALSE enable UDP long message protection
_skgxp_udp_timed_wait_buffering 1024 diagnostic log buffering space (in bytes) for timed wait (0 means unbufferd
_skgxp_udp_timed_wait_seconds 5 time in seconds before timed wait is invoked
_skgxp_udp_use_tcb TRUE disable use of high speek timer
_skip_assume_msg TRUE if TRUE, skip assume message for consigns at the master
_slave_mapping_enabled TRUE enable slave mapping when TRUE
_slave_mapping_group_size 0 force the number of slave group in a slave mapper
_small_table_threshold 541 threshold level of table size for direct reads
_smm_advice_enabled TRUE if TRUE, enable v$pga_advice
_smm_advice_log_size 0 overwrites default size of the PGA advice workarea history log
_smm_auto_cost_enabled TRUE if TRUE, use the AUTO size policy cost functions
_smm_auto_max_io_size 248 Maximum IO size (in KB) used by sort/hash-join in auto mode
_smm_auto_min_io_size 56 Minimum IO size (in KB) used by sort/hash-join in auto mode
_smm_bound 0 overwrites memory manager automatically computed bound
_smm_control 0 provides controls on the memory manager
_smm_freeable_retain 5120 value in KB of the instance freeable PGA memory to retain
_smm_isort_cap 102400 maximum work area for insertion sort(v1)
_smm_max_size 40960 maximum work area size in auto mode (serial)
_smm_min_size 204 minimum work area size in auto mode
_smm_px_max_size 102400 maximum work area size in auto mode (global)
_smm_retain_size 0 work area retain size in SGA for shared server sessions (0 for AUTO)
_smm_trace 0 Turn on/off tracing for SQL memory manager
_smon_internal_errlimit 100 limit of SMON internal errors
_smon_undo_seg_rescan_limit 10 limit of SMON continous undo segments re-scan
_smu_debug_mode 0 - set debug event for testing SMU operations
_smu_error_simulation_site 0 site ID of error simulation in KTU code
_smu_error_simulation_type 0 error type for error simulation in KTU code
_smu_timeouts comma-separated *AND double-quoted* list of AUM timeouts: mql, tur, sess_exprn, qry_exprn, slot_intvl
_sort_elimination_cost_ratio 0 cost ratio for sort eimination under first_rows mode
_sort_multiblock_read_count 2 multi-block read count for sort
_space_align_size 1048576 space align size
_spin_count 1 Amount to spin waiting for a latch
_spr_max_rules 10000 maximum number of rules in sql spreadsheet
_spr_push_pred_refspr TRUE push predicates through reference spreadsheet
_spr_use_AW_AS TRUE enable AW for hash table in spreadsheet
_spr_use_hash_table FALSE use hash table for spreadsheet
_sql_analyze_parse_model 2 SQL Analyze Parse Model control parameter
_sql_connect_capability_override 0 SQL Connect Capability Table Override
_sql_connect_capability_table SQL Connect Capability Table (testing only)
_sql_hash_debug 0 Hash value of the SQL statement to debug
_sql_model_unfold_forloops RUN_TIME specifies compile-time unfolding of sql model forloops
_sql_plan_baseline_capture_on_1_exec FALSE With auto-capture on, create new SQL plan baseline on first exec
_sqlexec_progression_cost 1000 sql execution progression monitoring cost threshold
_sqlmon_max_plan 20 Maximum number of plans entry that can be monitored. Defaults to 20 per CPU
_sqlmon_max_planlines 300 Number of plan lines beyond which a plan cannot be monitored
_sqlmon_threshold 5 CPU/IO time threshold before a statement is monitored. 0 is disabled
_sqltune_category_parsed DEFAULT Parsed category qualifier for applying hintsets
_srvntfn_job_deq_timeout 60 srvntfn job deq timeout
_srvntfn_jobsubmit_interval 3 srvntfn job submit interval
_srvntfn_max_concurrent_jobs 20 srvntfn max concurrent jobs
_srvntfn_q_msgcount 50 srvntfn q msg count for job exit
_srvntfn_q_msgcount_inc 100 srvntfn q msg count increase for job submit
_sscr_dir Session State Capture and Restore DIRectory object
_sscr_osdir Session State Capture and Restore OS DIRectory
_sta_control 0 SQL Tuning Advisory control parameter
_stack_guard_level 0 stack guard level
_static_backgrounds static backgrounds
_statistics_based_srf_enabled TRUE enable/disable the use of statistics for storage reduction factor
_step_down_limit_in_pct 1 step down limit in percentage
_stn_trace 0 SQL tracing parameter
_storage_predicate_access_predicate 0 put storage predicate into access predicate in explain plan
_streams_pool_max_size 0 streams pool maximum size when auto SGA enabled
_subquery_pruning_cost_factor 20 subquery pruning cost factor
_subquery_pruning_enabled TRUE enable the use of subquery predicates to perform pruning
_subquery_pruning_mv_enabled FALSE enable the use of subquery predicates with MVs to perform pruning
_subquery_pruning_reduction 50 subquery pruning reduction factor
_swrf_metric_frequent_mode FALSE Enable/disable SWRF Metric Frequent Mode Collection
_swrf_mmon_dbfus TRUE Enable/disable SWRF MMON DB Feature Usage
_swrf_mmon_flush TRUE Enable/disable SWRF MMON FLushing
_swrf_mmon_metrics TRUE Enable/disable SWRF MMON Metrics Collection
_swrf_on_disk_enabled TRUE Parameter to enable/disable SWRF
_swrf_test_action 0 test action parameter for SWRF
_swrf_test_dbfus FALSE Enable/disable DB Feature Usage Testing
_synonym_repoint_tracing FALSE whether to trace metadata comparisons for synonym repointing
_sysaux_test_param 1 test parameter for SYSAUX
_system_index_caching 0 optimizer percent system index caching
_system_trig_enabled TRUE are system triggers enabled
_ta_lns_wait_for_arch_log 20 LNS Wait time for arhcived version of online log
_table_lookup_prefetch_size 40 table lookup prefetch vector size
_table_lookup_prefetch_thresh 2 table lookup prefetch threshold
_table_scan_cost_plus_one TRUE bump estimated full table scan and index ffs cost by one
_target_rba_max_lag_percentage 90 target rba max log lag percentage
_tdb_debug_mode 16 set debug mode for testing transportable database
_temp_tran_block_threshold 100 number of blocks for a dimension before we temp transform
_temp_tran_cache TRUE determines if temp table is created with cache option
_test_ksusigskip 5 test the function ksusigskip
_test_param_1 25 test parmeter 1 – integer
_test_param_2 test parameter 2 – string
_test_param_3 test parameter 3 – string
_test_param_4 test parameter 4 – string list
_test_param_5 25 test parmeter 5 – deprecated integer
_test_param_6 0 test parmeter 6 – size (ub8)
_test_spacebg 0 test space management background task
_third_spare_parameter third spare parameter – integer
_threshold_alerts_enable 1 if 1, issue threshold-based alerts
_timemodel_collection TRUE enable timemodel collection
_timeout_actions_enabled TRUE enables or disables KSU timeout actions
_timer_precision 20 VKTM sleep time in milli-sec
_total_large_extent_memory 0 Total memory for allocating large extents
_tq_dump_period 0 time period for duping of TQ statistics (s)
_trace_buffer_wait_timeouts 0 trace buffer busy wait timeouts
_trace_buffers ALL:256 trace buffer sizes per process
_trace_dump_all_procs FALSE if TRUE on error buckets of all processes will be dumped to the current trace file
_trace_dump_client_buckets TRUE if TRUE dump client (ie. non-kst) buckets
_trace_dump_cur_proc_only FALSE if TRUE on error just dump our process bucket
_trace_dump_static_only FALSE if TRUE filter trace dumps to always loaded dlls
_trace_events trace events enabled at startup
_trace_files_public FALSE Create publicly accessible trace files
_trace_kqlidp FALSE trace kqlidp0 operation
_trace_navigation_scope global enabling trace navigation linking
_trace_pin_time 0 trace how long a current pin is held
_trace_pool_size trace pool size in bytes
_trace_processes ALL enable KST tracing in process
_trace_virtual_columns FALSE trace virtual columns exprs
_transaction_auditing TRUE transaction auditing records generated in the redo log
_transaction_recovery_servers 0 max number of parallel recovery slaves that may be used
_truncate_optimization_enabled TRUE do truncate optimization if set to TRUE
_tsenc_tracing 0 Enable TS encryption tracing
_tsm_connect_string TSM test connect string
_tsm_disable_auto_cleanup 1 Disable TSM auto cleanup actions
_tts_allow_charset_mismatch FALSE allow plugging in a tablespace with an incompatible character set
_two_pass TRUE enable two-pass thread recovery
_two_pass_reverse_polish_enabled TRUE uses two-pass reverse polish alg. to generate canonical forms
_uga_cga_large_extent_size 262144 UGA/CGA large extent size
_ultrafast_latch_statistics TRUE maintain fast-path statistics for ultrafast latches
_undo_autotune TRUE enable auto tuning of undo_retention
_undo_block_compression TRUE enable undo block compression
_undo_debug_mode 0 debug flag for undo related operations
_undo_debug_usage 0 invoke undo usage functions for testing
_union_rewrite_for_gs YES_GSET_MVS expand queries with GSets into UNIONs for rewrite
_unnest_subquery TRUE enables unnesting of correlated subqueries
_unused_block_compression TRUE enable unused block compression
_update_datafile_headers_with_space_information FALSE user requested update of datafile headers of locally managed datafiles with space information
_use_best_fit FALSE use best fit to allocate space
_use_column_stats_for_function TRUE enable the use of column statistics for DDP functions
_use_ism TRUE Enable Shared Page Tables – ISM
_use_ism_for_pga TRUE Use ISM for allocating large extents
_use_nosegment_indexes FALSE use nosegment indexes in explain plan
_use_realfree_heap TRUE use real-free based allocator for PGA memory
_use_seq_process_cache TRUE whether to use process local seq cache
_use_vector_post TRUE use vector post
_use_zero_copy_io TRUE Should network vector IO interface be used for data transfer
_validate_flashback_database FALSE Scan database to validate result of flashback database
_vendor_lib_loc Vendor library search root directory
_verify_flashback_redo TRUE Verify that the redo logs needed for flashback are available
_verify_undo_quota FALSE TRUE – verify consistency of undo quota statistics
_very_large_partitioned_table 1024 very_large_partitioned_table
_virtual_column_overload_allowed TRUE overload virtual columns expression
_wait_breakup_threshold_csecs 600 Wait breakup threshold (in centiseconds)
_wait_breakup_time_csecs 300 Wait breakup time (in centiseconds)
_wait_for_sync TRUE wait for sync on commit MUST BE ALWAYS TRUE
_walk_insert_threshold 0 maximum number of unusable blocks to walk across freelist
_watchpoint_on FALSE is the watchpointing feature turned on?
_wcr_control 0 Oracle internal test WCR parameter used ONLY for testing!
_windowfunc_optimization_settings 0 settings for window function optimizations
_with_subquery OPTIMIZER WITH subquery transformation
_write_clones 3 write clones flag
_xpl_peeked_binds_log_size 8192 maximum bytes for logging peeked bind values for V$SQL_PLAN (0 = OFF)
_xpl_trace 0 Explain Plan tracing parameter
_xsolapi_auto_materialization_bound 20 OLAP API lower bound for auto materialization.
_xsolapi_auto_materialization_type PRED_AND_RC OLAP API behavior for auto materialization
_xsolapi_build_trace FALSE OLAP API output build info to trace file
_xsolapi_debug_output SUPPRESS OLAP API debug output disposition
_xsolapi_densify_cubes TABULAR OLAP API cube densification
_xsolapi_dimension_group_creation OVERFETCH OLAP API symmetric overfetch
_xsolapi_dml_trace FALSE OLAP API output dml commands and expressions to trace file
_xsolapi_fetch_type PARTIAL OLAP API fetch type
_xsolapi_fix_vptrs FALSE OLAP API Enable vptr fixing logic in shared server mode
_xsolapi_generate_with_clause FALSE OLAP API generates WITH clause?
_xsolapi_hierarchy_value_type unique OLAP API hierarchy value type
_xsolapi_load_at_process_start NEVER When to load OLAP API library at server process start
_xsolapi_materialization_rowcache_min_rows_for_use 1 OLAP API min number of rows required to use rowcache in query materialization
_xsolapi_materialize_sources TRUE OLAP API Enable source materialization
_xsolapi_metadata_reader_mode 11_ONLY OLAP API metadata reader mode
_xsolapi_odbo_mode FALSE OLAP API uses ODBO mode?
_xsolapi_opt_aw_position TRUE OLAP API enables AW position and count optimization?
_xsolapi_optimize_suppression TRUE OLAP API optimizes suppressions?
_xsolapi_precompute_subquery TRUE OLAP API precomputes subqueries?
_xsolapi_remove_columns_for_materialization TRUE OLAP API removes columns for materialization?
_xsolapi_set_nls TRUE OLAP API sets NLS?
_xsolapi_share_executors TRUE OLAP API share executors?
_xsolapi_source_trace FALSE OLAP API output Source definitions to trace file
_xsolapi_sql_all_multi_join_non_base_hints OLAP API multi-join non-base hints
_xsolapi_sql_all_non_base_hints OLAP API non-base hints
_xsolapi_sql_auto_dimension_hints FALSE OLAP API enable automatic dimension hints
_xsolapi_sql_auto_measure_hints TRUE OLAP API enable automatic measure hints
_xsolapi_sql_dimension_hints OLAP API dimension hints
_xsolapi_sql_enable_aw_join TRUE OLAP API enables AW join?
_xsolapi_sql_enable_aw_qdr_merge TRUE OLAP API enables AW QDR merge?
_xsolapi_sql_hints OLAP API generic hints
_xsolapi_sql_measure_hints OLAP API measure hints
_xsolapi_sql_minus_threshold 1000 OLAP API SQL MINUS threshold
_xsolapi_sql_optimize TRUE OLAP API enable optimization
_xsolapi_sql_prepare_stmt_cache_size 16 OLAP API prepare statement cache size
_xsolapi_sql_remove_columns TRUE OLAP API enable remove unused columns optimizations
_xsolapi_sql_result_set_cache_size 32 OLAP API result set cache size
_xsolapi_sql_symmetric_predicate TRUE OLAP API enable symmetric predicate for dimension groups
_xsolapi_sql_top_dimension_hints OLAP API top dimension hints
_xsolapi_sql_top_measure_hints OLAP API top measure hints
_xsolapi_sql_use_bind_variables TRUE OLAP API enable bind variables optimization
_xsolapi_stringify_order_levels FALSE OLAP API stringifies order levels?
_xsolapi_support_mtm FALSE OLAP API MTM mapping classes supported?
_xsolapi_suppression_aw_mask_threshold 1000 OLAP API suppression AW mask threshold
_xsolapi_suppression_chunk_size 4000 OLAP API suppression chunk size
_xsolapi_use_models TRUE OLAP API uses models?
_xsolapi_use_olap_dml TRUE OLAP API uses OLAP DML?
_xsolapi_use_olap_dml_for_rank TRUE OLAP API uses OLAP DML for rank?
_xt_coverage none external tables code coverage parameter
_xt_trace none external tables trace parameter
_xtbuffer_size 0 buffer size in KB needed for populate/query operation
_xtts_allow_pre10 FALSE allow cross platform for pre10 compatible tablespace
_xtts_set_platform_info FALSE set cross platform info during file header read
_yield_check_interval 100000 interval to check whether actses should yield


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