NAME AVALUE SDESC _inmemory_check_prot_meta FALSE If true, marks SMU area read only to prevent stray writes _inmemory_private_journal_quota 100 quota for transaction in-memory private journals _inmemory_private_journal_sharedpool_quota 20
| NAME | AVALUE | SDESC |
| _inmemory_check_prot_meta | FALSE | If true, marks SMU area read only to prevent stray writes |
| _inmemory_private_journal_quota | 100 | quota for transaction in-memory private journals |
| _inmemory_private_journal_sharedpool_quota | 20 | quota for transaction in-memory objects |
| _inmemory_private_journal_numbkts | 512 | Number of priv jrnl ht bkts |
| _inmemory_private_journal_numgran | 128 | Number of granules per HT node |
| _inmemory_jscan | 0 | inmemory jscan enable |
| _inmemory_pin_hist_mode | 16 | settings for IM pinned buffer history |
| _inmemory_txn_checksum | 0 | checksum for SMUs and private journals |
| _inmemory_buffer_waittime | 100 | wait interval for one SMU or IMCU to be freed |
| _inmemory_cu_timeout | 100 | maximum wait time for one IMCU to be freed |
| _inmemory_cudrop_timeout | 1000 | maximum wait time for IMCU to be freed during drop |
| _inmemory_exclto_timeout | 1000 | maximum wait time to pin SMU for cleanout |
| _inmemory_num_hash_latches | 256 | Maximum number of latches for IM buffers |
| _inmemory_strdlxid_timeout | 0 | max time to determine straddling transactions |
| _inmemory_incremental_repopulation | FALSE | If true, incremental repopulation of IMCU will be attempted |
| _inmemory_lock_for_smucreate | FALSE | take object lock during smu creation |
| _inmemory_auto_distribute | TRUE | If true, enable auto distribute |
| _inmemory_autodist_2safe | FALSE | If true, enable auto distribute with 2safe |
| _inmemory_distribute_timeout | 300 | If true, enable auto distribute with 2safe |
| _inmemory_distribute_ondemand_timeout | 300 | On demand timeout for redistribute |
| inmemory_size | 0 | size in bytes of in-memory area |
| _inmemory_64k_percent | 30 | percentage of in-memory area for 64k pools |
| _inmemory_min_ima_defersize | 0 | Defer in-memory area allocation beyond this size |
| _inmemory_memprot | TRUE | enable or disable memory protection for in-memory |
| _inmemory_analyzer_optimize_for | 0 | inmemory analyzer optimize for |
| _inmemory_default_flags | 8459 | Default flags based on inmemory_clause_default |
| _inmemory_default_new | FALSE | Force in-memory on new tables |
| inmemory_clause_default | Default in-memory clause for new tables | |
| inmemory_force | DEFAULT | Force tables to be in-memory or not |
| inmemory_query | ENABLE | Specifies whether in-memory queries are allowed |
| _inmemory_query_scan | TRUE | In-memory scan enabled |
| _inmemory_scan_override | FALSE | In-memory scan override |
| _inmemory_scan_threshold_percent_noscan | 50 | In-memory scan threshold maximum percent dirty no scan |
| _inmemory_small_segment_threshold | 65536 | In-memory small segment threshold (must be larger for in-memory) |
| _inmemory_query_fetch_by_rowid | FALSE | In-memory fetch-by-rowid enabled |
| _inmemory_pruning | ON | In-memory pruning |
| _inmemory_enable_sys | FALSE | enable in-memory on system tablespace with sys user |
| _inmemory_populate_fg | FALSE | populate in foreground |
| _inmemory_pga_per_server | 536870912 | minimum pga needed per inmemory populate server |
| inmemory_max_populate_servers | 0 | maximum inmemory populate servers |
| _inmemory_servers_throttle_pgalim_percent | 55 | In-memory populate servers throttling pga limit percentage |
| inmemory_trickle_repopulate_servers_percent | 1 | inmemory trickle repopulate servers percent |
| _inmemory_populate_wait | FALSE | wait for population to complete |
| _inmemory_populate_wait_max | 600 | maximum wait time in seconds for segment populate |
| _inmemory_imco_cycle | 120 | IMCO cycle in seconds (sleep period) |
| _inmemory_enable_population_verify | 1 | verify in-memory population |
| _inmemory_log_level | 1 | in-memory log level |
| _inmemory_fs_verify | FALSE | in-memory faststart verify |
| _inmemory_force_fs | FALSE | in-memory faststart force |
| _inmemory_force_fs_tbs | SYSAUX | in-memory faststart force tablespace |
| _inmemory_force_fs_tbs_size | 1073741824 | in-memory faststart force tablespace size |
| _inmemory_fs_raise_error | FALSE | in-memory faststart raise error |
| _inmemory_fs_nodml | FALSE | in-memory faststart assumes no dmls while populating |
| _inmemory_fs_enable | FALSE | in-memory faststart enable |
| _inmemory_fs_enable_blk_lvl_inv | TRUE | in-memory faststart enable block level invalidation |
| _inmemory_fs_blk_inv_blkcnt | in-memory faststart CU invalidation threshold(blocks) | |
| _inmemory_fs_blk_inv_blk_percent | 20 | in-memory faststart CU invalidation threshold(blocks) |
| _inmemory_enable_stat_alert | FALSE | dump in-memory stats in alert log file |
| _inmemory_imcu_align | TRUE | Enforce 8M IMCU alignment |
| _inmemory_max_populate_retry | 3 | IM populate maximum number of retry |
| _inmemory_imcu_target_rows | 1048576 | IMCU target number of rows |
| _inmemory_imcu_target_bytes | 0 | IMCU target size in bytes |
| _inmemory_imcu_source_extents | 0 | number of source extents per IMCU |
| _inmemory_imcu_source_blocks | 0 | number of source blocks per IMCU |
| _inmemory_imcu_source_minbytes | 1048576 | number of minimum source bytes per IMCU |
| _inmemory_imcu_populate_minbytes | 5242880 | minimum free space in IMA for populating IMCU |
| _inmemory_imcu_source_analyze_bytes | 134217728 | number of source analyze bytes per IMCU |
| _inmemory_imcu_target_maxrows | 8388608 | IMCU maximum target number of rows |
| _inmemory_imcu_source_maxbytes | 536870912 | IMCU maximum source size in bytes |
| _inmemory_max_queued_tasks | 0 | Maximum queued populating tasks on the auxiliary queue |
| _inmemory_repopulate_threshold_rows | In-memory repopulate threshold number of modified rows | |
| _inmemory_repopulate_threshold_blocks | In-memory repopulate threshold number of modified blocks | |
| _inmemory_pct_inv_rows_invalidate_imcu | 50 | In-memory percentage invalid rows for IMCU invalidation |
| _inmemory_pct_inv_blocks_invalidate_imcu | 100 | In-memory percentage invalid blocks for IMCU invalidation |
| _inmemory_repopulate_threshold_mintime_factor | 5 | In-memory repopulate minimum interval (N*timetorepop) |
| _inmemory_repopulate_threshold_mintime | 0 | In-memory repopulate minimum interval (millisec) |
| _inmemory_repopulate_threshold_scans | 0 | In-memory repopulate threshold number of scans |
| _inmemory_repopulate_priority_scale_factor | 100 | In-memory repopulate priority threshold scale factor |
| _inmemory_repopulate_invalidate_rate_percent | 100 | In-memory repopulate invalidate rate percent |
| _inmemory_repopulate_priority_threshold_row | 20 | In-memory repopulate priority threshold row |
| _inmemory_repopulate_priority_threshold_block | 40 | In-memory repopulate priority threshold block |
| _inmemory_repopulate_threshold_rows_percent | 5 | In-memory repopulate threshold rows invalid percentage |
| _inmemory_repopulate_threshold_blocks_percent | 10 | In-memory repopulate threshold blocks invalid percentage |
| _inmemory_repopulate_disable | FALSE | disable In-memory repopulate |
| _inmemory_check_protect | FALSE | If true, marks in-memory area read only to prevent stray writes |
| _inmemory_checksum | FALSE | If true, checksums in-memory area to detect stray writes |
| _inmemory_validate_fetch | FALSE | If true, validate single-row fetch between in-memory and disk |
| _inmemory_journal_row_logging | FALSE | If true, log the entire row into the in-memory journal |
| _inmemory_journal_check | 0 | Depending on value does one of the DML verifications |
| _inmemory_rows_check_interrupt | 1000 | Number of rows buffered before interrupt check |
| _inmemory_dbg_scan | 0 | In-memory scan debugging |
| _inmemory_segment_populate_verify | 0 | In-memory segment populate verification |
| _inmemory_query_check | 0 | In-memory query checking |
| _inmemory_test_verification | 0 | In-memory verification testing |
| _inmemory_invalidate_cursors | TRUE | In-memory populate enable cursor invalidations |
| _inmemory_prepopulate_fg | 0 | Force prepopulate of in-memory segment in foreground |
| _inmemory_prepopulate | TRUE | Enable inmemory populate by IMCO |
| _inmemory_trickle_repopulate | TRUE | Enable inmemory trickle repopulate |
| _inmemory_trickle_repopulate_threshold_dirty_ratio | 0 | IMCO Trickle Repopulate threshold dirty ratio |
| _inmemory_trickle_repopulate_min_interval | 300 | IMCO Trickle Repopulate Interval |
| _inmemory_trickle_repopulate_fg | 0 | Trickle Repopulate in the Foreground |
| _inmemory_force_non_engineered | FALSE | force non-engineered systems in-memory behavior on RAC |
| _inmemory_suppress_vsga_ima | FALSE | Suppress inmemory area in v$sga |
| optimizer_inmemory_aware | TRUE | optimizer in-memory columnar awareness |
| _optimizer_inmemory_table_expansion | TRUE | optimizer in-memory awareness for table expansion |
| _optimizer_inmemory_gen_pushable_preds | TRUE | optimizer generate pushable predicates for in-memory |
| _optimizer_inmemory_autodop | TRUE | optimizer autoDOP costing for in-memory |
| _optimizer_inmemory_access_path | TRUE | optimizer access path costing for in-memory |
| _optimizer_inmemory_quotient | 0 | in-memory quotient (% of rows in in-memory format) |
| _optimizer_inmemory_pruning_ratio_rows | 100 | in-memory pruning ratio for # rows (% of rows remaining after pruning) |
| _parallel_inmemory_min_time_threshold | AUTO | threshold above which a plan is a candidate for parallelization for in-memory tables (in seconds) |
| _parallel_inmemory_time_unit | 1 | unit of work used to derive the degree of parallelism for in-memory tables (in seconds) |
| _optimizer_inmemory_bloom_filter | TRUE | controls serial bloom filter for in-memory tables |
| _optimizer_inmemory_cluster_aware_dop | TRUE | Affinitize DOP for inmemory objects |
| _optimizer_inmemory_minmax_pruning | TRUE | controls use of min/max pruning for costing in-memory tables |
test
In-Memory Database Cache
IM in-memory ((null))
IM_transaction IM transaction layer ((null))
IM_Txn_PJ IM Txn Private Journal (ktmpj)
IM_Txn_SJ IM Txn Shared Journal (ktmsj)
IM_Txn_JS IM Txn Journal Scan (ktmjs)
IM_Txn_Conc IM Txn Concurrency (ktmc)
IM_Txn_Blk IM Txn Block (ktmb)
IM_Txn_Read IM Txn Read (ktmr)
IM_space IM space layer ((null))
IM_data IM data layer (kdm)
IM_populate IM populating (kdml)
IM_background IM background (kdmr)
IM_scan IM scans ((null))
IM_journal IM journal ((null))
IM_dump IM dump ((null))
IM_FS IM faststart ((null))
IM_optimizer IM optimizer (kdmo)
alter session set events 'trace[IM_scan] disk=medium';
SQL> alter system set inmemory_size=2g scope=spfile;
System altered.
SQL> shutdown immediate;
[oracle@mlab2 ~]$ sqlplus / as sysdba
SQL*Plus: Release 12.1.0.2.0 Production on Wed Sep 3 23:18:18 2014
Copyright (c) 1982, 2014, Oracle. All rights reserved.
Connected to an idle instance.
SQL> startup;
ORACLE instance started.
Total System Global Area 2684354560 bytes
Fixed Size 2928008 bytes
Variable Size 402653816 bytes
Database Buffers 117440512 bytes
Redo Buffers 13848576 bytes
In-Memory Area 2147483648 bytes
Database mounted.
Database opened.
alter session set events 'trace[IM_scan] disk=medium';
select count(*) from mac_imm1;
SQL> oradebug setmypid
Statement processed.
SQL> oradebug tracefile_name
/s01/diag/rdbms/c12r1/C12R1/trace/C12R1_ora_16700.trc
kdmsirs(): map with 13 extents
Ext: 0, dba: 0x18000db, len: 5, skp: 0
Ext: 1, dba: 0x18000e0, len: 8, skp: 0
Ext: 2, dba: 0x18000e9, len: 7, skp: 0
Ext: 3, dba: 0x18000f0, len: 8, skp: 0
Ext: 4, dba: 0x18000f9, len: 7, skp: 0
Ext: 5, dba: 0x1800100, len: 8, skp: 0
Ext: 6, dba: 0x1800109, len: 7, skp: 0
Ext: 7, dba: 0x1800110, len: 8, skp: 0
Ext: 8, dba: 0x1800119, len: 7, skp: 0
Ext: 9, dba: 0x1800120, len: 8, skp: 0
Ext: 10, dba: 0x1800129, len: 7, skp: 0
Ext: 11, dba: 0x1800130, len: 8, skp: 0
Ext: 12, dba: 0x1800139, len: 1, skp: 0
kdmsStartEndDBA(): scan start: 0x18000db end: 0x18000df rdba[0]: 0x18000db size[0]: 5, nblks: 5 extno: 0, skip: 0
kdmsGetIMCU(): In arguments: nblks 5: start_addr 25166043, end_addr 25166047
kdmsGetIMCU(): Mem addr: baffffd0: mem len: 1048576: Start dba: 0x18000db 25166043: len: 5 smu: fbf44770 td: 0x7f76515361a8
kdmsGetIMCU(): range: 0 lrid dba: 0x0 slot: 0 hrid dba: 0x0 slot: 0
kdmsGetIMCU(): found imcu 0xbaffffd0 25166043 25166047 1
kdst_fetch_imc(): imcu get 0x18000db
kdmsTransGet(): got ktmrds for dba 0x18000db, td : 0x7f76515361a8
kdmsFindEndDba: ext in imcu is 0, and on disk 0
IMCU extents
extent 0: 25166043 0x18000db + 5
extent 1: 25166048 0x18000e0 + 8
extent 2: 25166057 0x18000e9 + 7
extent 3: 25166064 0x18000f0 + 8
extent 4: 25166073 0x18000f9 + 7
extent 5: 25166080 0x1800100 + 8
extent 6: 25166089 0x1800109 + 7
extent 7: 25166096 0x1800110 + 8
extent 8: 25166105 0x1800119 + 7
extent 9: 25166112 0x1800120 + 8
extent 10: 25166121 0x1800129 + 7
extent 11: 25166128 0x1800130 + 8
extent 12: 25166137 0x1800139 + 1
Disk extents
extent 0: 25166043 0x18000db + 5 (skip = 0)
extent 1: 25166048 0x18000e0 + 8 (skip = 0)
extent 2: 25166057 0x18000e9 + 7 (skip = 0)
extent 3: 25166064 0x18000f0 + 8 (skip = 0)
extent 4: 25166073 0x18000f9 + 7 (skip = 0)
extent 5: 25166080 0x1800100 + 8 (skip = 0)
extent 6: 25166089 0x1800109 + 7 (skip = 0)
extent 7: 25166096 0x1800110 + 8 (skip = 0)
extent 8: 25166105 0x1800119 + 7 (skip = 0)
extent 9: 25166112 0x1800120 + 8 (skip = 0)
extent 10: 25166121 0x1800129 + 7 (skip = 0)
extent 11: 25166128 0x1800130 + 8 (skip = 0)
extent 12: 25166137 0x1800139 + 1 (skip = 0)
kdmsFindEndDba(): begin: 25166043, end dba: 25166137 done ext in imcu 12 on disk 12
min of imcu end 25166138 0x180013a disk end 25166138 0x180013a discont 0
kdst_fetch_imc(): done: 1, empty: 0, ftch: 0
kdst_fetch_imc(): fetch: 0, invalid: 0
kdmsRepopulate(): repop 0 nblks 89 0 nrows 2342 0 cnt 5
kdstf00100010001101kmP(): create vv 18000db 95
kdmsCreateIMCUValidVector: Scan range (25166043, 25166137)
Extent map passed into kdzd layer:
Extent 0: (25166043, 25166047)
Extent 1: (25166048, 25166055)
Extent 2: (25166057, 25166063)
Extent 3: (25166064, 25166071)
Extent 4: (25166073, 25166079)
Extent 5: (25166080, 25166087)
Extent 6: (25166089, 25166095)
Extent 7: (25166096, 25166103)
Extent 8: (25166105, 25166111)
Extent 9: (25166112, 25166119)
Extent 10: (25166121, 25166127)
Extent 11: (25166128, 25166135)
Extent 12: (25166137, 25166137)
kdzd_dump_validvec:
IMCU: 1
Num slots: 2342 set: 2342 rounded to 8: 2368 bytes: 296
Flag if all rows valid: 1
ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.
ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.
ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.
ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.
ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.
ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.
ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.
ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.
ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.
ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.
ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.
ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.ff.3f.
3 final 0
kdzd_dump_validvec: End Dumping Valid Vector
**************** ktmrDS Dump *****************
pdb=0, tsn=4, rdba=25166043, objn=91999, objd=91999, typ=1, gflg=0 flg=0
loadscn=scn: 0x0000.001af80b
invalid blkcnt=0, fetch blkcnt=0
env [0x7f765152af6c]: (scn: 0x0000.001af830 xid: 0x0000.000.00000000 uba: 0x00000000.0000.00 statement num=0 parent xid: 0x0000.000.00000000 st-scn: 0x0000.00000000 hi-scn: 0x0000.00000000 ma-scn: 0x0000.001af82c flg: 0x00000660)invalid rowcnt=0,
fetch rowcnt=0
kdst_fetch_imc(): release 0x18000db from td: 0x7f76515361a8
kdmsGetJournalRows(): done with IMC fetch; journal rows -1
kdmsEnd(): imcuctx 0x7f7651688b78 release 0x18000db from td: 0x7f76515361a8
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原文地址：【Oracle 12c】In-Memory Database Cache内存数据库选项, 感谢原作者分享。
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Penyingkiran pakaian AI
AI Hentai Generator
Menjana ai hentai secara percuma.
Artikel Panas
Alat panas
VSCode Windows 64-bit Muat Turun
Editor IDE percuma dan berkuasa yang dilancarkan oleh Microsoft
EditPlus versi Cina retak
Saiz kecil, penyerlahan sintaks, tidak menyokong fungsi gesaan kod
SublimeText3 Linux versi baharu
SublimeText3 Linux versi terkini
Dreamweaver CS6
Alat pembangunan web visual
DVWA
Damn Vulnerable Web App (DVWA) ialah aplikasi web PHP/MySQL yang sangat terdedah. Matlamat utamanya adalah untuk menjadi bantuan bagi profesional keselamatan untuk menguji kemahiran dan alatan mereka dalam persekitaran undang-undang, untuk membantu pembangun web lebih memahami proses mengamankan aplikasi web, dan untuk membantu guru/pelajar mengajar/belajar dalam persekitaran bilik darjah Aplikasi web keselamatan. Matlamat DVWA adalah untuk mempraktikkan beberapa kelemahan web yang paling biasa melalui antara muka yang mudah dan mudah, dengan pelbagai tahap kesukaran. Sila ambil perhatian bahawa perisian ini
