前回に続き、Oracle Database19cと23cの隠しパラメータを比較した結果を纏めた最終回。今回は19cと比較して23cで新規に登場した隠しパラメータのうち、最後に残った_s～_zから始まる隠しパラメータを記載する。
※19cとの比較による新規隠しパラメータの抽出であるため、20c,21cで新規登場したものも23cでの新規として記載する。隠しパラメータ数が多いため、PCでの閲覧推奨。
5.新規隠しパラメータ(_s* ～ _z*)
新規の隠しパラメータは1388個存在し、_s* ～ _z*な隠しパラメータは232個存在した。
| パラメータ名 | デフォルト値 | ALTER SESSION | ALTER SYSTEM | パラメータ概要 |
|---|---|---|---|---|
| _saga_clear_interval | 86400 | FALSE | IMMEDIATE | qmon periodic interval for processing saga clearing job |
| _saga_timeout_interval | 3600 | FALSE | IMMEDIATE | qmon periodic interval for processing saga timeout |
| _saga_timeout_operation_type | rollback | FALSE | IMMEDIATE | operation type when a saga expires |
| _scheduler_cjq0_buffer_size | 1024 | FALSE | IMMEDIATE | buffer size (in KB) for scheduler IMT for CJQ process |
| _scheduler_inmemory_trace_timeout | 600 | TRUE | IMMEDIATE | Timeout for scheduler internal operations |
| _scheduler_jnnn_buffer_size | 32 | FALSE | IMMEDIATE | buffer size (in KB) for scheduler IMT for JNNN processes |
| _scheduler_ora_buffer_size | 32 | TRUE | IMMEDIATE | buffer size (in KB) for scheduler IMT for ORA processes |
| _search_space_from_beginning | 2147483647 | FALSE | IMMEDIATE | search free space from the beginning of a tablespace |
| _second_spare_pdb_parameter | TRUE | IMMEDIATE | second spare pdb parameter - integer | |
| _securefile_shrink_enable_nowaitlck | FALSE | TRUE | IMMEDIATE | Enable Securefile Shrink NOWAIT row locking |
| _securefile_shrink_hash_table_limit | 100 | FALSE | IMMEDIATE | Size limit on Securefile Lob Shrink state Hash table |
| _securefiles_dealloc_cfs | 0 | FALSE | FALSE | securefiles deallocate directly to CFS |
| _sensitive_fixed_invalidate | NONE | FALSE | IMMEDIATE | Invalidate sensitive policy fixed object dependent cursors |
| _service_internal_gateway | TRUE | IMMEDIATE | service name registered with Net Listener on Internal Gateway | |
| _sess_sign_num_pools | 16 | FALSE | FALSE | session signature: number of pools |
| _sess_template_all_overflow | FALSE | TRUE | IMMEDIATE | session template: put all attributes into overflow |
| _sess_template_cache_buckets | 128 | FALSE | FALSE | session template: number of cache buckets |
| _sess_template_enabled | TRUE | TRUE | IMMEDIATE | session template: enabled |
| _sess_template_max_cache_size | 5 | FALSE | IMMEDIATE | session template: max cache size (in 1/100% of SGA) |
| _sess_template_new_lists | 16 | FALSE | FALSE | session template: number of new lists |
| _sess_template_purge_time_mins | 60 | FALSE | IMMEDIATE | session template: purge time (in minutes) |
| _session_limit_percent_cap | 25 | FALSE | IMMEDIATE | session limit percent cap |
| _session_modp_list | 2 | FALSE | IMMEDIATE | send session's modified parameter list to client |
| _session_preserve_logon_container | FALSE | TRUE | FALSE | preserve the logon container id in the session |
| _session_so_max_inc | 20000 | FALSE | IMMEDIATE | session SO max inc |
| _seventeenth_spare_pdb_parameter | TRUE | IMMEDIATE | seventeenth spare pdb parameter - integer | |
| _seventh_spare_pdb_parameter | TRUE | IMMEDIATE | seventh spare pdb parameter - integer | |
| _seventieth_spare_pdb_parameter | TRUE | TRUE | IMMEDIATE | seventieth spare pdb parameter - boolean |
| _shard_cached_sessions | 0 | FALSE | IMMEDIATE | session cache size for cross shard SQLs |
| _shard_ddl_policy | ASYNC | TRUE | IMMEDIATE | DDL execution mode for shards |
| _shard_enable_serialized_ddl | TRUE | TRUE | IMMEDIATE | enable workload-serialized DDL in Oracle Sharding Replication |
| _shard_repl_max_iobuf | 256 | FALSE | FALSE | max number of snr io buffers |
| _shard_sesscache_cnt | 0 | FALSE | IMMEDIATE | enable session caching for shard SQL |
| _shard_size_per_raft_logfile_gb | 1 | FALSE | IMMEDIATE | size of raft log file in GB |
| _sharding_lockdown | FALSE | FALSE | IMMEDIATE | Oracle internal parameter |
| _shared_pool_lru_bufs | 200 | FALSE | IMMEDIATE | shared pool lru effort buffer size |
| _shared_spfile_check | FALSE | FALSE | parameter to validate shared spfile | |
| _shutdown_abort_timeout_mins | 0 | TRUE | IMMEDIATE | minutes for shutdown operation to wait for completion before initiating shutdown abort |
| _singleton_service_goodness_disabled | TRUE | FALSE | IMMEDIATE | singleton srvc goodness |
| _sixteenth_spare_pdb_parameter | TRUE | IMMEDIATE | sixteenth spare pdb parameter - integer | |
| _sixth_spare_pdb_parameter | TRUE | IMMEDIATE | sixth spare pdb parameter - integer | |
| _sixtieth_spare_pdb_parameter | TRUE | TRUE | IMMEDIATE | sixtieth spare pdb parameter - boolean |
| _sixty-eighth_spare_pdb_parameter | TRUE | TRUE | IMMEDIATE | sixty-eighth spare pdb parameter - boolean |
| _sixty-fifth_spare_pdb_parameter | TRUE | TRUE | IMMEDIATE | sixty-fifth spare pdb parameter - boolean |
| _sixty-first_spare_pdb_parameter | TRUE | TRUE | IMMEDIATE | sixty-first spare pdb parameter - boolean |
| _sixty-fourth_spare_pdb_parameter | TRUE | TRUE | IMMEDIATE | sixty-fourth spare pdb parameter - boolean |
| _sixty-ninth_spare_pdb_parameter | TRUE | TRUE | IMMEDIATE | sixty-ninth spare pdb parameter - boolean |
| _sixty-second_spare_pdb_parameter | TRUE | TRUE | IMMEDIATE | sixty-second spare pdb parameter - boolean |
| _sixty-seventh_spare_pdb_parameter | TRUE | TRUE | IMMEDIATE | sixty-seventh spare pdb parameter - boolean |
| _sixty-sixth_spare_pdb_parameter | TRUE | TRUE | IMMEDIATE | sixty-sixth spare pdb parameter - boolean |
| _sixty-third_spare_pdb_parameter | TRUE | TRUE | IMMEDIATE | sixty-third spare pdb parameter - boolean |
| _skip_adding_plsql_negative_dep | FALSE | TRUE | IMMEDIATE | If enabled then skip adding plsql negative dependency |
| _skip_cursor_syspriv_rechecks | FALSE | FALSE | IMMEDIATE | skip re-authorization of session cached cursors |
| _skip_fixed_dependency_load_during_drop | FALSE | TRUE | IMMEDIATE | skip load of fixed object dependency during drop |
| _skip_multiple_svc_netname_convert_patterns | FALSE | TRUE | IMMEDIATE | skip apply multiple patterns on a network name during service_name_convert in PDB |
| _skip_oradism_check | FALSE | FALSE | FALSE | Switch on all features for the purpose of testing |
| _skip_pdbid | TRUE | IMMEDIATE | PDBIDs to be skipped during init of kpdblist from control file | |
| _skip_sequence_cache_close_immediate | FALSE | TRUE | IMMEDIATE | Skip sequence cache flush on pdb shutdown immediate |
| _skippriv_emailserver_credential | FALSE | FALSE | IMMEDIATE | Skip execute privilege check on scheduler email server credential |
| _slave_mapping_skew_handling | TRUE | TRUE | IMMEDIATE | enables skew handling for slave mapping plans |
| _slow_kill_rate_on_pdb_close_immediate | 5 | TRUE | FALSE | Rate of killing sessions gradually on pdb close immediate |
| _smart_scan_object_size_threshold | 0 | TRUE | IMMEDIATE | lower threshold of object size in MB for smartscan offload |
| _smm_low_mem_bound_diag_threshold | 0 | FALSE | IMMEDIATE | low memory bound threshold to trigger diagnostic dump |
| _smon_ofd_sleep_interval | 300 | FALSE | IMMEDIATE | smon sleep internval for undo ofd test |
| _smon_sort_management | 0 | FALSE | FALSE | Control SMON or SMCO process sort segment management message |
| _spec_replace_locks_body | TRUE | TRUE | IMMEDIATE | Lock body when replacing a package specification |
| _spfile_comment_validation_mode | DISABLE | FALSE | IMMEDIATE | Validate parameter comment format |
| _split_app_current_state | FALSE | FALSE | IMMEDIATE | Use _CURRENT_STATE_CDB object to sync CDB-wide apps |
| _sql_analysis | TRUE | TRUE | IMMEDIATE | enable SQL analysis for reporting in plan |
| _sql_error_mitigation_control | 0 | TRUE | IMMEDIATE | internal controls for auto error mitigation |
| _sql_error_mitigation_repeat_wait | 86400 | TRUE | IMMEDIATE | minimum wait time (seconds) between repeated mitigations |
| _sql_error_mitigation_retention | 365 | FALSE | IMMEDIATE | Auto error mitigation diagnostic tables retention period |
| _sql_error_mitigation_time_limit | 600 | TRUE | IMMEDIATE | maximum time limit (seconds) for error mitigation |
| _sql_history_buffers | 50 | FALSE | IMMEDIATE | Min number of sql query history buffers to be monitored |
| _sql_plan_management_comp_metric | 3 | TRUE | IMMEDIATE | controls metric used in comparing performance of plans in SPM |
| _sqlexec_aggregation_settings | 0 | TRUE | IMMEDIATE | runtime settings for aggregation |
| _sqlexec_hash_aggr_small_mem_blocks | 2 | TRUE | IMMEDIATE | hash aggregation small initial memory footprint number of blocks |
| _sqlexec_hash_based_distagg_ser_civ_enabled | TRUE | TRUE | IMMEDIATE | enable hash based distinct aggregation in serial/CIV queries |
| _sqlexec_hash_based_set_operation_enabled | TRUE | TRUE | IMMEDIATE | enable/disable hash based set operation |
| _sqlexec_hash_rollup_enabled | TRUE | TRUE | IMMEDIATE | enable hash rollup |
| _sqlexec_use_delayed_unpacking | TRUE | TRUE | IMMEDIATE | enable/disable the usage of delayed unpacking |
| _sqlexec_window_function_settings | 63 | TRUE | IMMEDIATE | execution settings for window functions |
| _sqlmon_conitr_row_cache_size | 50 | TRUE | IMMEDIATE | Max rows fetched from keomnRefreshCacheFromPdbSwitchCbk() |
| _sqlmon_max_active_idle | 0 | TRUE | IMMEDIATE | Time (in sec) after which a SQL Monitor entry can be reclaimed |
| _srvntfn_max_job_time | 180 | FALSE | IMMEDIATE | srvntfn max time per job |
| _standby_parse_limit_seconds | 0 | TRUE | IMMEDIATE | Standby parse time limit (seconds) |
| _standby_temp_file_management | AUTO | FALSE | IMMEDIATE | tempfile management on standby databases |
| _statement_redirect_host | NONE | FALSE | IMMEDIATE | statement redirect host |
| _statement_redirect_routing_function | NONE | FALSE | IMMEDIATE | statement redirect routing function |
| _STFForceTranslateOracleSQL | FALSE | FALSE | IMMEDIATE | if TRUE translation profile will translate Oracle SQL statements |
| _strict_utl_http_smtp | FALSE | TRUE | IMMEDIATE | Enforce strict URL checks on UTL_HTTP and UTL_SMTP Packages |
| _subname_for_object_patching | NONE | TRUE | IMMEDIATE | subname used to create a duplicate object for patching |
| _subquery_pruning_flags | 0 | TRUE | IMMEDIATE | subquery pruning flags |
| _subseg_debug | 0 | TRUE | IMMEDIATE | KTSV Subseg Debug |
| _subseg_quiesce_threshold | 10240 | TRUE | IMMEDIATE | KTSV threshold size for loading to new subseg in MB |
| _suppress_pg_population | FALSE | TRUE | IMMEDIATE | If true, all graph populations are suppressed |
| _swat_ver_mv_knob | 0 | TRUE | FALSE | Knob to control MV/REWRITE behavior |
| _symbol_no_translation | FALSE | TRUE | IMMEDIATE | disable symbol tranlations in call stacks |
| _sync_error_handler | TRUE | IMMEDIATE | error handler function for Application Sync | |
| _synchronous_rewrap_rac_ts_keys | FALSE | FALSE | IMMEDIATE | if TRUE, synchronously rewrap TS keys in all nodes in MK rekey |
| _system_memory_simulate | FALSE | FALSE | FALSE | system memory simulation mode, TRUE for hugetlbfs simulation |
| _table_func_pred_pushdown | FALSE | TRUE | IMMEDIATE | enable table function predicate pushdown |
| _tablespace_encryption_cipher_mode | CFB | FALSE | IMMEDIATE | default tablespace encryption block cipher mode |
| _target_offload | FALSE | FALSE | IMMEDIATE | enable target offload functionality |
| _target_offload_algorithm | random | TRUE | IMMEDIATE | algorithm for choosing target for offload |
| _tcpinfo_statistics_save_atexit | FALSE | TRUE | IMMEDIATE | TCP Info Statistics Save At Exit |
| _temp_undo_disable_refresh_clone | FALSE | TRUE | IMMEDIATE | is temp undo disabled on refreshable clone PDB |
| _tempfile_monitor_interval | 3600 | FALSE | IMMEDIATE | tempfile monitor interval in seconds |
| _tenth_spare_pdb_parameter | TRUE | IMMEDIATE | tenth spare pdb parameter - integer | |
| _test_flashback_shrink | 0 | FALSE | IMMEDIATE | test flashback datafile shrink feature |
| _test_param_13 | FALSE | TRUE | IMMEDIATE | test parmeter 13 - boolean |
| _test_param_14 | NONE | TRUE | IMMEDIATE | test parmeter 14 - string list |
| _test_param_15 | 50 | TRUE | IMMEDIATE | test parmeter 15 - integer |
| _test_param_16 | 500 | TRUE | IMMEDIATE | test parmeter 16 - integer |
| _test_param_4_1 | NONE | TRUE | FALSE | test parameter 4_1 - nonsys mod. string list |
| _test_param_pdb_spare | TRUE | IMMEDIATE | test parameter pdb spare | |
| _test_param_spare | TRUE | IMMEDIATE | test parameter spare | |
| _text_batch_num | 32 | FALSE | FALSE | Text number of batches |
| _text_batch_size | 8 | FALSE | FALSE | Text batch size in Mb |
| _text_datastore_access | FALSE | FALSE | IMMEDIATE | Oracle Text alternate datastore default settings |
| _text_estat_purge | 30 | TRUE | IMMEDIATE | Text event stats purge interval in days |
| _text_event_sizing | 3 | FALSE | FALSE | Text event sizing level |
| _text_maintenance | auto | FALSE | FALSE | Text default maintenance setting |
| _tgtt_single_segment | FALSE | FALSE | FALSE | Whether to use single segment for trans GTTs |
| _third_spare_pdb_parameter | TRUE | IMMEDIATE | third spare pdb parameter - integer | |
| _thirteenth_spare_pdb_parameter | TRUE | IMMEDIATE | thirteenth spare pdb parameter - integer | |
| _thirtieth_spare_pdb_parameter | TRUE | IMMEDIATE | thirtieth spare pdb parameter - string | |
| _thirty-eighth_spare_pdb_parameter | TRUE | IMMEDIATE | thirty-eighth spare pdb parameter - string | |
| _thirty-fifth_spare_pdb_parameter | TRUE | IMMEDIATE | thirty-fifth spare pdb parameter - string | |
| _thirty-first_spare_pdb_parameter | TRUE | IMMEDIATE | thirty-first spare pdb parameter - string | |
| _thirty-fourth_spare_pdb_parameter | TRUE | IMMEDIATE | thirty-fourth spare pdb parameter - string | |
| _thirty-ninth_spare_pdb_parameter | TRUE | IMMEDIATE | thirty-ninth spare pdb parameter - string | |
| _thirty-second_spare_pdb_parameter | TRUE | IMMEDIATE | thirty-second spare pdb parameter - string | |
| _thirty-seventh_spare_pdb_parameter | TRUE | IMMEDIATE | thirty-seventh spare pdb parameter - string | |
| _thirty-sixth_spare_pdb_parameter | TRUE | IMMEDIATE | thirty-sixth spare pdb parameter - string | |
| _thirty-third_spare_pdb_parameter | TRUE | IMMEDIATE | thirty-third spare pdb parameter - string | |
| _threaded_execution | FALSE | FALSE | FALSE | Threaded Execution Mode Internal |
| _time_threshold_to_reboot_mmon_slv | 86400 | FALSE | IMMEDIATE | Time threshold to reboot MMON slave processes |
| _tkh_in_fsc_per_ts | 5 | FALSE | FALSE | Max tkh records stored in FSC per table space |
| _trace_suppress | TRUE | IMMEDIATE | suppresses matching trace for a given substring(prefix) | |
| _trace_suppress_disable | FALSE | FALSE | FALSE | Disable trace suppress feature |
| _tregex_compilation_dump_graph_on_crash | FALSE | TRUE | IMMEDIATE | dump compilation graphs to the trace file when compilation crashes in TRegex |
| _tregex_compilation_errors_are_fatal | FALSE | TRUE | IMMEDIATE | failed compilations are fatal for TRegex |
| _tregex_enable_compilation | TRUE | FALSE | IMMEDIATE | enable runtime compilation for TRegex |
| _true_cache_aff_hash_latches | 16 | FALSE | FALSE | True Cache affinity table latches |
| _true_cache_block_fetch_abort_timeout | 20000 | TRUE | IMMEDIATE | True Cache block fetch abort time out in centiseconds |
| _true_cache_block_fetch_latency_histogram | TRUE | TRUE | IMMEDIATE | Enable True Cache block fetch latency histogram |
| _true_cache_block_fetch_latency_limit | 5000 | TRUE | IMMEDIATE | True Cache block fetch latency in usec considered too large |
| _true_cache_block_fetch_timeout | 300 | TRUE | IMMEDIATE | True Cache block fetch time out in centiseconds |
| _true_cache_chore_mask | 0 | FALSE | FALSE | True Cache health chore mask |
| _true_cache_config | NONE | FALSE | IMMEDIATE | True cache config |
| _true_cache_dest | NONE | FALSE | IMMEDIATE | True Cache destinations server list |
| _true_cache_disc_time | 86400 | FALSE | FALSE | True Cache disconnect time |
| _true_cache_heartbeat_interval | 60 | FALSE | FALSE | True Cache heartbeat interval |
| _true_cache_lad_max_failure | 20 | FALSE | FALSE | True Cache max LAD failures |
| _true_cache_lad_nettimeout | 30 | FALSE | FALSE | True Cache LAD net timeout time |
| _true_cache_lad_reopen | 15 | FALSE | FALSE | True Cache LAD reopen time |
| _true_cache_latch_less_htab | FALSE | FALSE | FALSE | Latchless affinity hash table access |
| _true_cache_max_block_fetch_requests | 1024 | TRUE | IMMEDIATE | True Cache maximum outstanding block fetch requests |
| _true_cache_max_payload | 1048576 | FALSE | FALSE | True Cache max batch payload size |
| _true_cache_max_unapplied_logs | 10 | FALSE | FALSE | True Cache max unapplied log files |
| _true_cache_num_batch_requests | 4 | FALSE | FALSE | True Cache number of request to batch |
| _true_cache_num_dsndr_process | 2 | FALSE | FALSE | True Cache number of data send process |
| _true_cache_num_fch_process | 2 | FALSE | FALSE | True Cache number of data request process |
| _true_cache_payload_size | 65536 | FALSE | FALSE | True Cache RMI payload size |
| _true_cache_pdb_disc_time | 3600 | FALSE | FALSE | True Cache PDB disconnect time |
| _true_cache_preallocate_num_request | 1024 | FALSE | FALSE | True Cache number of request to preallocate |
| _true_cache_temp_file_ext | 10 | FALSE | FALSE | True Cache default temp file extend |
| _true_cache_temp_file_size | 100 | FALSE | FALSE | True Cache default temp file size |
| _tsq_shared_enabled | TRUE | TRUE | IMMEDIATE | Enable shared mode on tsq |
| _ttc_annotations_level | 0 | FALSE | IMMEDIATE | enable ttc annotations |
| _tune_kctncv_diff_limit | 134217728 | FALSE | FALSE | Self-tune kctvncv diff limit for MTTR |
| _twelfth_spare_pdb_parameter | TRUE | IMMEDIATE | twelfth spare pdb parameter - integer | |
| _twentieth_spare_pdb_parameter | TRUE | IMMEDIATE | twentieth spare pdb parameter - integer | |
| _twenty-eighth_spare_pdb_parameter | TRUE | IMMEDIATE | twenty-eighth spare pdb parameter - string | |
| _twenty-fifth_spare_pdb_parameter | TRUE | IMMEDIATE | twenty-fifth spare pdb parameter - string | |
| _twenty-first_spare_pdb_parameter | TRUE | IMMEDIATE | twenty-first spare pdb parameter - string | |
| _twenty-fourth_spare_pdb_parameter | TRUE | IMMEDIATE | twenty-fourth spare pdb parameter - string | |
| _twenty-ninth_spare_pdb_parameter | TRUE | IMMEDIATE | twenty-ninth spare pdb parameter - string | |
| _twenty-second_spare_pdb_parameter | TRUE | IMMEDIATE | twenty-second spare pdb parameter - string | |
| _twenty-seventh_spare_pdb_parameter | TRUE | IMMEDIATE | twenty-seventh spare pdb parameter - string | |
| _twenty-sixth_spare_pdb_parameter | TRUE | IMMEDIATE | twenty-sixth spare pdb parameter - string | |
| _twenty-third_spare_pdb_parameter | TRUE | IMMEDIATE | twenty-third spare pdb parameter - string | |
| _two_phase_rac_rolling_prepare_timeout | 60 | FALSE | IMMEDIATE | Prepare callback timeout for 2-Phase Rac Rolling in Seconds |
| _txn_max_quarantines | 3 | FALSE | IMMEDIATE | Max number of transaction that can be quarantined |
| _txn_spare1 | 0 | TRUE | IMMEDIATE | transaction spare variable1 |
| _txn_spare2 | 0 | TRUE | IMMEDIATE | transaction spare variable2 |
| _txn_spare3 | 0 | TRUE | IMMEDIATE | transaction spare variable3 |
| _txn_trace_bucket_memory_location | PGA | FALSE | IMMEDIATE | Determines if Transaction Layer default bucket will be allocated in PGA or SGA |
| _txn_trace_bucket_size | 16384 | FALSE | IMMEDIATE | Txn layer trace bucket size |
| _txn_trace_buckets | FALSE | IMMEDIATE | Status of transaction layer buckets | |
| _um_huge_page_min_pct | 60 | FALSE | FALSE | Min percent of shared memory in UM backed by large pages |
| _undo_ofd_enabled | TRUE | FALSE | IMMEDIATE | enable ordered offline drop of undo segments for datafile shrink |
| _undo_ofd_excess | 10 | FALSE | IMMEDIATE | percent of excess undo segments to offline or drop |
| _undo_ofd_reserve | 30 | FALSE | IMMEDIATE | percent of excess undo segments to keep online |
| _unified_memory_heap_mask | 2 | FALSE | FALSE | enable use of unified memory for these heaps |
| _unified_memory_pga_lim_pct | 40 | FALSE | FALSE | Percentage of pga limit in Unified Memory |
| _unified_memory_private_pct | 20 | FALSE | FALSE | Percentage of private memory in Unified Memory |
| _unified_memory_shared_pct | 80 | FALSE | FALSE | Percentage of shared memory in Unified Memory |
| _unified_pdb_shared_pct | 60 | FALSE | IMMEDIATE | UM Shared memory percent for a PDB |
| _unified_pga_alloc_wait_timeout | 10000 | FALSE | IMMEDIATE | UM allocation wait timeout |
| _unified_pga_block_size | 262144 | FALSE | FALSE | Unified PGA internal block size |
| _unified_pga_gran_free_timeout | 3000 | FALSE | IMMEDIATE | Granule free timeout |
| _unified_pga_gran_leak_timeout | 180000 | FALSE | IMMEDIATE | Granule leak timeout |
| _unified_pga_list_count | 16 | FALSE | FALSE | Unified PGA internal list count |
| _unified_pga_max_pool_size | 0 | FALSE | IMMEDIATE | max size in bytes of the unified pga pool |
| _upgrade_pdb_on_open | TRUE | TRUE | IMMEDIATE | Enable upgrading a PDB automatically on open |
| _use_aes128_redo_encryption | FALSE | FALSE | IMMEDIATE | If true, use AES128 encryption for redo |
| _use_kradc_fetch | FALSE | TRUE | IMMEDIATE | if TRUE, use kradc per process sync block fetch |
| _use_pseudo_policy | TRUE | FALSE | IMMEDIATE | use pseudo policy for sensitive data handling |
| _use_saga_qtyp | 0 | FALSE | IMMEDIATE | Queue type used in SAGA infrastructure |
| _use_shared_capture | FALSE | FALSE | IMMEDIATE | Enable GoldenGate Extracts to use Shared Capture Service |
| _use_stored_fgd | TRUE | TRUE | IMMEDIATE | Enable use of stored fine-grained delta for invalidations |
| _use_text_large_pages | TRUE | FALSE | FALSE | Use large pages for text if available |
| _ut_fast_lrg_prediction | FALSE | FALSE | FALSE | use short interval for session SO prediction |
| _utlfile_dirpath | FALSE | FALSE | FALSE | return Utl_File Accessible |
| _uts_disable_client_ip_trace | FALSE | FALSE | IMMEDIATE | Disables the printing of client IP address in trace files |
| _uxt_cloud_delete_on_drop_table | TRUE | TRUE | IMMEDIATE | Delete cloud files on drop of updatable external table |
| _uxt_credential | TRUE | IMMEDIATE | credential name used for updatable external table data | |
| _uxt_diag_flags | 0 | TRUE | IMMEDIATE | flags to enable diagnostics for updatable external tables |
| _uxt_uri_prefix | TRUE | IMMEDIATE | URI prefix for updatable external tables | |
| _verify_db_blocks_after_encrypt | FALSE | FALSE | IMMEDIATE | if TRUE, decrypt each block after encryption to verify encrypt |
| _wait_stats_cpus_per_set | 16 | FALSE | FALSE | Wait event stats: number of cpus per set |
| _write_renamed_datafile_name | FALSE | TRUE | IMMEDIATE | print renamed datafile names to alert log |
| _xa_parameters | TRUE | IMMEDIATE | Exascale parameters | |
| _xs_max_retries_lib_lock | 30 | FALSE | IMMEDIATE | Maximum number of retries to get lib lock |
| _xs_sidp_allow_sha1 | TRUE | FALSE | IMMEDIATE | XS SIDP allow use of SHA1 |
| _xt_hybrid_addl_hidden_column | FALSE | TRUE | IMMEDIATE | enable additional hidden columns for external/hybrid table |
| _xt_table_hidden_column | FALSE | TRUE | IMMEDIATE | enable hidden columns for external table |
| _zonemap_auto_candidate_table_min_size | 5000 | FALSE | IMMEDIATE | Minimum size for a table to be candidate for an automatic zonemap |
| _zonemap_auto_clustering_ratio | 50 | FALSE | IMMEDIATE | Data clustering ratio in percent for automatic zonemap columns |
| _zonemap_refresh_within_load | TRUE | TRUE | IMMEDIATE | Control the refresh of basic zonemaps during/after data load |
最後に。隠しパラメータの変更した場合、製品サポートを受けられなくなる可能性があるため、実際に変更する際は、Oracle Databaseのサポート契約先に問合せした後に実施することをお勧めする。
前回の記事：Oracle19cと23cの隠しパラメータの差分について調べてみた ～その5～
