당신은 주제를 찾고 있습니까 “enq ro fast object reuse – 3 46 Su dung Object browser de tra cuu trong VBA Su dung Object browser de tra cuu trong VBA“? 다음 카테고리의 웹사이트 https://chewathai27.com/you 에서 귀하의 모든 질문에 답변해 드립니다: https://chewathai27.com/you/blog. 바로 아래에서 답을 찾을 수 있습니다. 작성자 Công nghệ và Kiến thức 이(가) 작성한 기사에는 조회수 1회 및 좋아요 없음 개의 좋아요가 있습니다.
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Oracle: enq: RO – fast object reuse – Embarcadero DB Optimizer
Oracle: enq: RO – fast object reuse. reusable object- clearing cache for object drop/reuse, use gtt if possible, tune DBWR …
Source: sites.google.com
Date Published: 11/21/2022
View: 2647
Session waiting for “enq: RO – fast object reuse” – Martin Decker
A user session has been waiting for “enq: RO – fast object reuse” for almost 60 minutes while executing a “truncate table” SQL statement.
Source: www.ora-solutions.net
Date Published: 1/22/2022
View: 4491
enq: RO – fast object reuse | DBmarlin Docs and Knowledge Base
enq: RO – fast object reuse. Short Description. Enqueue wait. Object reuse. Search online. If this article doesn’t have the information you need you can …
Source: docs.dbmarlin.com
Date Published: 9/2/2022
View: 6277
‘enq: RO – fast object reuse’ and ‘enq: KO – On Oracle
The RO enqueue known as “Multiple object reuse” enqueue, is used to synchronise operations between foreground process and a background process …
Source: ksun-oracle.blogspot.com
Date Published: 9/11/2021
View: 7724
Truncate table slow enq: ro – Fast Object Reuse and local …
Truncate table slow enq: ro – Fast Object Reuse and local write wait wait wait for analysis. 2021-07-28 04:14:48 【zhjh256】.
Source: chowdera.com
Date Published: 9/29/2021
View: 5973
DLM cross inst call completion | enq: RO – fast object reuse …
The enq: RO – fast object reuse enqueue known as “Multiple object resue” enqueue, is used to synchronise operations between foreground process …
Source: ittutorial.org
Date Published: 10/29/2022
View: 532
Tag Archives: enq: RO – fast object reuse – vjdba
A user session has been waiting for “enq: RO – fast object reuse” for almost 60 minutes while executing a “truncate table” SQL statement.
Source: vjdba.wordpress.com
Date Published: 9/5/2022
View: 9533
Oracle local write wait and enq:RO-fast object reuse wait for the …
You see waiting events for local write waits and enq: RO-fast object reuse in AWR. . . .I. Local write waits for instructions. .online description of the …
Source: codeandcache.com
Date Published: 10/26/2021
View: 1522
주제와 관련된 이미지 enq ro fast object reuse
주제와 관련된 더 많은 사진을 참조하십시오 3 46 Su dung Object browser de tra cuu trong VBA Su dung Object browser de tra cuu trong VBA. 댓글에서 더 많은 관련 이미지를 보거나 필요한 경우 더 많은 관련 기사를 볼 수 있습니다.
주제에 대한 기사 평가 enq ro fast object reuse
- Author: Công nghệ và Kiến thức
- Views: 조회수 1회
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- Date Published: 2022. 7. 7.
- Video Url link: https://www.youtube.com/watch?v=KTX0LRr1BtI
Session waiting for “enq: RO – fast object reuse” – DBWR Process spinning on CPU
I have encountered the following problem on a 10.2.0.4 database on Linux x86_64 today:
A user session has been waiting for “enq: RO – fast object reuse” for almost 60 minutes while executing a “truncate table” SQL statement.
SQL> select username, event, sql_id, taddr, last_call_et from v$session where sid = 234; USERNAME EVENT SQL_ID TADDR LAST_CALL_ET
———- —————————– ————- —————- ————
MD enq: RO – fast object reuse ljk299jlkj003 0000000153264570 3542 SQL> select sql_text from v$sqlstats where sql_id = ‘ljk299jlkj003’; SQL_TEXT
————————————-
truncate table tab1
The Session was blocked by the CKPT process:
SQL> select * from dba_waiters; WAITING_SESSION HOLDING_SESSION LOCK_TYPE MODE_HELD MODE_REQUESTED LOCK_ID1 LOCK_ID2
————— ————— ————————– —————————————- —————————————- ———- ———-
234 423 RO Row-S (SS) Exclusive 65573 1 SQL> select sid, serial#, sql_id, last_call_et, machine, program, username from v$session where sid = 423; SID SERIAL# SQL_ID LAST_CALL_ET MACHINE PROGRAM
———- ———- ————- ———— —————- ——————————–
423 1 4133636 ora-vm1.intra [email protected] (CKPT)
The checkpoint process was waiting for database writer DBWR process, which was spinning on one cpu:
top
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
10712 oracle 25 0 2201m 1.7g 1.7g R 99.5 21.7 108:18.03 oracle
PID 10712 maps to DBW0:
[oracle@ora-vm1 ]$ ps -ef|grep 10712oracle 10712 1 0 2008 ? 03:23:05 ora_dbw0_MDDB01
mpstat
Linux 2.6.9-78.ELsmp (ora-vm1.intra) 01/20/2009 02:21:56 PM CPU %user %nice %system %iowait %irq %soft %idle intr/s
02:21:57 PM all 49.75 0.00 0.00 0.00 0.00 0.00 50.25 1055.00
02:21:57 PM 0 0.00 0.00 0.00 0.00 0.00 0.00 100.00 1006.00
02:21:57 PM 1 100.00 0.00 0.00 0.00 0.00 0.00 0.00 49.00 02:21:57 PM CPU %user %nice %system %iowait %irq %soft %idle intr/s
02:21:58 PM all 50.75 0.00 0.00 0.50 0.00 0.00 48.76 1161.00
02:21:58 PM 0 1.00 0.00 0.00 1.00 0.00 0.00 98.00 1087.00
02:21:58 PM 1 100.00 0.00 0.00 0.00 0.00 0.00 0.00 74.00
The stack of dbw0 during the time showed these signatures:
[oracle@ora-vm1 oracle]$ pstack 10712#0 0x000000000074b7fb in kslfre ()
#1 0x00000000010ccc3b in kcbo_exam_buf ()
#2 0x00000000010d0d62 in kcbo_service_ockpt ()
#3 0x0000000001080cd7 in kcbbdrv ()
#4 0x00000000007ddcc2 in ksbabs ()
#5 0x00000000007e4b32 in ksbrdp ()
#6 0x0000000002efcb50 in opirip ()
#7 0x00000000012da326 in opidrv ()
#8 0x0000000001e62456 in sou2o ()
#9 0x00000000006d2555 in opimai_real ()
#10 0x00000000006d240c in main ()
[oracle@ora-vm1 oracle]$ pstack 10712#0 0x000000000074b36d in kslfre ()
#1 0x00000000010cc203 in kcbo_write_process ()
#2 0x00000000010ce608 in kcbo_write_q ()
#3 0x0000000001080a6d in kcbbdrv ()
#4 0x00000000007ddcc2 in ksbabs ()
#5 0x00000000007e4b32 in ksbrdp ()
#6 0x0000000002efcb50 in opirip ()
#7 0x00000000012da326 in opidrv ()
#8 0x0000000001e62456 in sou2o ()
#9 0x00000000006d2555 in opimai_real ()
#10 0x00000000006d240c in main ()
[oracle@ora-vm1 oracle]$ pstack 10712#0 0x00000000010ccb60 in kcbo_exam_buf ()
#1 0x00000000010d0d62 in kcbo_service_ockpt ()
#2 0x0000000001080cd7 in kcbbdrv ()
#3 0x00000000007ddcc2 in ksbabs ()
#4 0x00000000007e4b32 in ksbrdp ()
#5 0x0000000002efcb50 in opirip ()
#6 0x00000000012da326 in opidrv ()
#7 0x0000000001e62456 in sou2o ()
#8 0x00000000006d2555 in opimai_real ()
#9 0x00000000006d240c in main ()
[oracle@ora-vm1 oracle]$ pstack 10712#0 0x00000000010d0da5 in kcbo_service_ockpt ()
#1 0x0000000001080cd7 in kcbbdrv ()
#2 0x00000000007ddcc2 in ksbabs ()
#3 0x00000000007e4b32 in ksbrdp ()
#4 0x0000000002efcb50 in opirip ()
#5 0x00000000012da326 in opidrv ()
#6 0x0000000001e62456 in sou2o ()
#7 0x00000000006d2555 in opimai_real ()
#8 0x00000000006d240c in main ()
A MetaLink Research for the term “kcbo_service_ockpt” leads to Bug 7376934, which is a duplicate of Bug 7385253 – DBWR IS CONSUMING HIGH CPU.
Patch 7385253 is available for Linux x86_64, HP-UX, Solaris, AIX.
Reference:
MetaLink Note 762085.1 – Subject: ‘enq: RO – fast object reuse’ contention when gathering schema/table statistics in parallel
enq: RO – fast object reuse
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enq: RO – fast object reuse
Short Description Enqueue wait. Object reuse.
If this article doesn’t have the information you need you can try searching online. Remember, you can contribute suggestions to this page.
Fast Object Reuse and local write wait wait wait for analysis
Use ASSM Table space （ The default mode ） When , stay dss There will be… In the system truncate Very slow phenomenon , But he won’t 100% repeat , It depends on probability . adopt sql trace（ To any v$sysstat It seems that the resource consumption is very low , Both can pass sql trace Find the root cause , therefore sql trace It is a necessary tool for analyzing but not necessarily helping solve problems ） You can see how internal time is consumed . about truncate, Because we haven’t directly met , No analysis , But in FDA When I met , By the way, I searched （FDA There are other reasons , See other posts on this blog ）,truncate The reasons why it is slow are as follows ：
Here’s one that started off with a tweet from Kevin Closson, heading towards a finish that shows some interesting effects when you truncate large objects that are using ASSM. To demonstrate the problem I’ve set up a tablespace using system allocation of extents and automatic segment space management (ASSM). It’s the ASSM that causes the problem, but it requires a mixture of circumstances to create a little surprise.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 create tablespace test_8k_auto_assm datafile — OMF SIZE 1030M autoextend off blocksize 8k extent management local autoallocate segment space management auto ; create table t1 (v1 varchar2(100)) pctfree 99 tablespace test_8k_auto_assm storage(initial 1G); insert into t1 select user from dual; commit; alter system flush buffer_cache; truncate table t1;
I’ve created a table with an initial definition of 1GB, which means that (in a clean tablespace) the autoallocate option will jump straight to extents of 64MB, with 256 table blocks mapped per bitmap block for a total of 32 bitmap blocks in each 64MB extent. Since I’m running this on 11.2.0.4 and haven’t included “segment creation immediate” in the definition I won’t actually see any extents until I insert the first row.
So here’s the big question – when I truncate this table (using the given command) how much work will Oracle have to do ?
Exchanging notes over twitter (140 char at a time) and working from a model of the initial state, it took a little time to get to understand what was (probably) happening and then produce this silly example – but here’s the output from a snapshot of v$session_event for the session across the truncate:
1 2 3 4 5 6 7 8 9 Event Waits Time_outs Csec Avg Csec Max Csec —– —– ——— —- ——– ——– local write wait 490 0 83.26 .170 13 enq: RO – fast object reuse 2 0 104.90 52.451 105 db file sequential read 47 0 0.05 .001 0 db file parallel read 8 0 0.90 .112 0 SQL*Net message to client 10 0 0.00 .000 0 SQL*Net message from client 10 0 0.67 .067 153 events in waitclass Other 2 0 0.04 .018 109
The statistic I want to highlight is the number recorded against “local write wait”: truncating a table of one row we wait for 490 blocks to be written! We also have 8 “db file parallel read” waits which, according to a 10046 trace file, were reading hundreds of blocks. (I think the most significant time in this test – the RO enqueue wait – may have been waiting for the database writer to complete the work needed for an object checkpoint, but I’m not sure of that.)
The blocks written were the space management bitmap blocks for the extent(s) that remained after the truncate – even the ones that referenced extents above the high water mark for the table. Since we had set the tables initial storage to 1GB, we had a lot of bitmap blocks. At 32 per extent and 16 extents (64MB * 16 = 1GB) we might actually expect something closer to 512 blocks, but actually Oracle had formatted the last extent with only 8 space management blocks. and the first extent had an extra 2 to cater for the level 2 bitmap lock and segment header block giving: 32 * 15 + 8 + 2 = 490.
As you may have seen above, the impact on the test that Kevin was doing was quite dramatic – he had set the initial storage to 128GB (lots of bitmap blocks), partitioned the table (more bitmap blocks) and was running RAC (so the reads were running into waits for global cache grants).
I had assumed that this type of behaviour happened only with the “reuse storage” option of the truncate command: and I hadn’t noticed before that it also appeared even if you didn’t reuse storage – but that’s probably because the effect applies only to the bit you keep, which may typically mean a relatively small first extent. It’s possible, then, that in most cases this is an effect that isn’t going to be particularly visible in production systems – but if it is, can you work around it ? Fortunately another tweeter asked the question “What happens if you ‘drop all storage?’”
truncate There are three options , as follows ：
DROP STORAGE , the default option, reduces the number of extents allocated to the resulting table to the original setting for MINEXTENTS . Freed extents are then returned to the system and can be used by other objects.
DROP ALL STORAGE drops the segment. In addition to the TRUNCATE TABLE statement, DROP ALL STORAGE also applies to the ALTER TABLE TRUNCATE (SUB)PARTITION statement. This option also drops any dependent object segments associated with the partition being truncated. DROP ALL STORAGE is not supported for clusters.
Note: This functionality is available with Oracle Database 11 g release 2 (11.2.0.2). TRUNCATE TABLE emp DROP ALL STORAGE;
REUSE STORAGE specifies that all space currently allocated for the table or cluster remains allocated to it. For example, the following statement truncates the emp_dept cluster, leaving all extents previously allocated for the cluster available for subsequent inserts and deletes: TRUNCATE CLUSTER emp_dept REUSE STORAGE;
Here’s the result from adding that clause to my test case:
1 2 3 4 5 6 7 8 Event Waits Time_outs Csec Avg Csec Max Csec —– —– ——— —- ——– ——– enq: RO – fast object reuse 1 0 0.08 .079 0 log file sync 1 0 0.03 .031 0 db file sequential read 51 0 0.06 .001 0 SQL*Net message to client 10 0 0.00 .000 0 SQL*Net message from client 10 0 0.56 .056 123 events in waitclass Other 3 0 0.87 .289 186
Looking good – if you don’t keep any extents you don’t need to make sure that their bitmaps are clean. (The “db file sequential read” waits are almost all about the data dictionary, following on from my “flush buffer cache”).
Footnote
The same effect appears in 12.1.0.2
Footnote 2
It’s interesting to note that the RO enqueue wait time seems to parallel the local write wait time: perhaps a hint that there’s some double counting going on. (To be investigated, one day).
Footnote 3 (June 2018)
The same effect appears in 12.2.0.1
enq: RO – fast object reuse wait event and _db_fast_obj_truncate parameter during Truncate Table in Oracle 19c – IT Tutorial
DLM cross inst call completion | enq: RO – fast object reuse wait event and _db_fast_obj_truncate parameter during Truncate Table in Oracle 19c
Hi,
I will explain DLM cross inst call completion and enq: RO – fast object reuse wait event during Truncate Table in Oracle 19c in this post.
You can read the following post to learn more details about Wait event and their solution.
DLM cross inst call completion
Truncate table command is waiting because of DLM cross inst call completion wait event, and this command is completed about 4-5 hours in Oracle 19c.
enq: RO – fast object reuse
The enq: RO – fast object reuse enqueue known as “Multiple object resue” enqueue, is used to synchronise operations between foreground process and a background process such as DBWR or CKPT. It is typically used when dropping objects or truncating tables.
Following is the sequence of events When a truncate/drop occurs:
Foreground process acquires the “RO” enqueue in exclusive mode Cross instance calls (or one call if it is a single object) are issued (“CI” enqueue is acquired) CKPT processes on each of instances requests the DBWR to write the dirty buffers to the disk and invalidate all the clean buffers. After DBWR completes writing all blocks, the foreground process releases the RO enqueue
_db_fast_obj_truncate Parameter and Truncate Table
You can set the following parameter for workaround solution.
Alter system set “_db_fast_obj_truncate”=false scope=both sid=’*’;
If the _db_fast_obj_truncate parameter don’t solve your problem, then apply the permanent solution as follows.
This two wait events are being investigated by internal Bug 31208287 and Bug 31038220 in Oracle 19c.
Details of bug and patch are in the following Oracle Support Note.
Drop User Cascade Command Hang On “DLM cross inst call completion” (Doc ID 2671064.1)
To solve this error, download the following patches for Oracle 19c from Oracle Support, then apply this patches.
p31038220_198000DBRU_Linux-x86-64
p31208287_198000DBRU_Linux-x86-64
After applying these two patches, set the following parameter, then truncate table command will run fastly.
Our truncate table is run 4-5 minutes after these steps.
Alter system set “_db_fast_obj_truncate”=true scope=both sid=’*’;
Do you want to learn Oracle Database Performance Tuning detailed, then read the following articles.
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enq: RO – fast object reuse
I have encountered the following problem on a 10.2.0.4 database on AIX 5.3 x86_64 today:
A user session has been waiting for “enq: RO – fast object reuse” for almost 60 minutes while executing a “truncate table” SQL statement.
SQL> select username, event, sql_id, taddr, last_call_et from v$session where sid = 1086;
USERNAME EVENT SQL_ID TADDR LAST_CALL_ET
———- —————————————- ————- —————- ————
STSC enq: RO – fast object reuse 4y213r2udxp9z 0700000109250A40 5304
SQL> select sql_text from v$sqlstats where sql_id = ‘4y213r2udxp9z’;
SQL_TEXT
——————————————–
truncate table stsc.planarriv
The Session was blocked by the CKPT process:
SQL> select * from dba_waiters;
WAITING_SESSION HOLDING_SESSION LOCK_TYPE MODE_HELD MODE_REQUESTED LOCK_ID1 LOCK_ID2
————— ————— ————————– —————————————- —————————————- ———- ———-
1086 1099 RO Row-S (SS) Exclusive 65613 1
SQL> select sid, serial#, sql_id, last_call_et, machine, program, username from v$session where sid=1099;
SID SERIAL# SQL_ID LAST_CALL_ET MACHINE PROGRAM USERNAME
———- ———- ————- ———— ———————— ———————————————— ———-
1099 1 9831952 ksfrprddb01 oracle@ksfrprddb01 (CKPT)
Issue is because of the Bug 7385253 – Slow Truncate / DBWR uses high CPU / CKPT blocks on RO enqueue.
Below are the symptoms for this bug.
1. Truncate will wait on “enq: RO – fast object reuse” wait event.
2. CKPT process will block truncate table session.
3. At OS level DBWR will be using 100% CUP.
Temporary fix:
1) Flushing the buffer cache.
OR
2) Setting “_db_fast_obj_truncate” =FALSE.
— ALTER SYSTEM SET “_db_fast_obj_truncate”=FALSE SCOPE=BOTH;
NOTE: Setting the parameter “_db_fast_obj_truncate” will revert back to 9i way of invalidating buffers in buffercache. This could have an impact on performance.Kindly note that both workarounds(flushing shared pool and setting the underscore parameter)could have an impact on the database performance.Instead, it is recommended applying the corresponding patch.
Permanent Fix:
1. Install Patch having number 7385253
References :
10.2.0.4 Slowness: High DBW* CPU Usage with ‘Enq: RO – FAST OBJECT REUSE’ and ( High DFS Lock Handle ID1=3 in RAC) [ID 888844.1]
‘enq: RO – fast object reuse’ contention when gathering schema/table statistics in parallel [ID 762085.1]
Oracle local write wait and enq:RO-fast object reuse wait for the event description
Oracle local write wait and enq:RO-fast object reuse wait for the event description
You see waiting events for local write waits and enq: RO-fast object reuse in AWR.
I. . Local write waits for instructions
online description of the local write waits:
Note 1 ：
Typically DBWRhas to free up some buffers when you want to read something from the disk. During this process there are chances that you will be waiting for your localbuffer (i.e blocks dirtied/invalidated by your session) to be written to disk. During this time the waits are shown as local write waits .
Note 2 ：
Basically ‘localwrite’ wait happens (as the name indicates) when the session is waiting for itslocal (means writes pending because of its own operation) writeoperation. This could happen typically if the underlying disc has some seriousproblems (one of the member disk crash in RAID-05 – for example, or acontroller failure). That is why I might have said ‘ you never see this wait inthe normal databases!’. You may see thisduring (rarely) Truncating a large table while most of the buffers of thattable in cache. During TRUNCATEs the session has to a local checkpoint andduring this process, the session may wait for ‘local write’ wait.
Basically ‘local write’ waits to indicate that the session is waiting for its own write. Serious problems with the disk occur (such as a disk crash in RAID 5, or a disk controller error), which is rare in a normal system, when THE ISTRUATE is a large table and this table is in the cache, the session must perform a logarcheckpoint, at which point the session waits for the lossesion wait.
DOCUMENTS IN MOS:
Truncates Taking Too Long… [ID 334822.1]
this waiting event was mentioned.
Cause ：
Processes thatinvolve temporary tables being truncated and repopulated in multiple,concurrent batch streams may present this situation.
The underlyingproblem is we have to write the object’s dirty buffers to disk prior toactually truncating or dropping the object. This ensures instancerecoverability and avoids a stuck recovery. It seems at first glance perfectlyreasonable to simply truncate a temporary table, then repopulate for anotherusage. And then to do the temporary poplulate/truncate operationsin concurrent batches to increase throughput.
However, inreality the concurrent truncates get bogged down as dbwr gets busy flushing thosedirty block buffers from the buffer cache. You will see huge CI enqueue waits. The multiple truncate operations in concurrent streams absolutely killthroughput. This is specially critical with large buffers.
There was also adisscussion in Bug: 4147840 (non-publish) where a peoplesoft process wascausing this behavior because of the above explanation and they seemed to fixit by changing some peoplesoft code to implement delete rather than truncate onsamll temporary tables.
Solution ：
In 9.2.0.5 andhigher, it may also help to make sure a “temp” table that isfrequently truncated have storage defined so that it occupies one extent. But this workaround is only available as long as the extent is no morethan 50% the size of the buffer cache. In non-RAC environments the tablestill has to be smaller than 50% of the buffer cache, but it allows thetable to have up to 5 extents before falling back to the old algorithm.
II. enq: RO – fast reuse object waits for an event
this wait event is mostly bug-related
2.1 Bug 1 ： Bug 7385253
Bug 7385253 – Slow Truncate / DBWR useshigh CPU / CKPT blocks on RO enqueue [ID 7385253.8]
Product ( Component ) Oracle Server (Rdbms) Range of versions believed to be affected Versions >= 10 but BELOW 11.2 Versions confirmed as being affected 11.1.0.7
10.2.0.4
10.2.0.3
10.2.0.2 Platforms affected Generic (all / most platforms affected)
The bug’s 3 manifestations:
(1) Hang(Involving Shared Resource)
(2) PerformanceAffected (General)
(3) Waits for ” enq:RO – fast object reuse ”
DBWR may use alot of CPU and seem to spin in or around kcbo_write_qdue to large number offree buffers on the object reuse queue or checkpoint queue.
In some casesthe CKPT holds the RO enqueue for very long blocking other operations with waitevent “enq: RO – fast objectreuse”.
Operations so farreported being affected are :
– Apply Processes in StandBy databases
– Gather stats
– Truncates
– drop/shrink/alter tablespace
Note: This fix was previously incorrectlylisted as not affecting 11g.
The bug itself is present in 11g but it is unlikely to show anysignificant symptom due to other 11g changes meaning that free buffers are nolonger kept on the object queue.
Workaround with the bug:
setting _db_fast_obj_truncate=FALSE <--did not fix the issue enabling asyn i/o <-- customer refused to implement to avoid corruptionsrisk applying 7287289 <-- did not fix the issue 2.2 document ii 'enq: RO - fastobject reuse' contention when gathering schema/table statistics in parallel [ID762085.1] Symptoms ： （1）Database has been recently upgradedfrom 10.2.0.1 to 10.2.0.4. （2）There is 'enq: RO - fastobject reuse' contention when gathering schema/table statistics in parallelusing DBMS_STATS package (with DEGREE>1).
It is also because bug 7385253 causes this problem.
solution:
1) Flushing the buffer cache.
OR
2) Setting “_db_fast_obj_truncate” =FALSE. This reverts back to the9i way of invalidating buffers in the buffer cache.
Kindly note thatboth workarounds could have an impact on the database performance. Instead, itis recommended applying the corresponding patch.
— both of these workarounds have a significant impact on db performance, and it is recommended that you apply the appropriate patch.
2.3 document iii
Bug8544896 – Waits for “enq: RO – fast object reuse” with high DBWR CPU[ID 8544896.8]
Product ( Component ) Oracle Server (Rdbms) Range of versions believed to be affected Versions >= 10.2.0.4 but BELOW 10.2.0.5 Versions confirmed as being affected 10.2.0.4 Platforms affected Generic (all / most platforms affected)
It is believed to be a regression in default behaviour thus:
Regression introduced in 10.2.0.4
This problem is introduced in 10.2.0.4.
Sessions can wait on “enq: RO – fastobject reuse” while DBWR consumes lots of CPU when performing truncatetype operations.
Workaround:
（1）Flush the buffer cache beforetruncating
OR
（2） set _db_fast_obj_truncate = FALSE.
The two wait events that I have here are related to the Truncate operation.
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——- The group needs to explain the relationship between the Oracle table space and the data file in the note, otherwise the request is rejected —-
DBA1 GROUP: 62697716 (FULL); DBA2 GROUP: 62697977 (FULL) DBA3 GROUP: 62697850 (FULL)
DBA SUPERGROUP: 63306533 (FULL); DBA4 GROUP: 83829929 DBA5 GROUP: 142216823
DBA6 GROUP: 158654907 DBA7 GROUP: 172855474 DBA TOTAL: 104207940
키워드에 대한 정보 enq ro fast object reuse
다음은 Bing에서 enq ro fast object reuse 주제에 대한 검색 결과입니다. 필요한 경우 더 읽을 수 있습니다.
이 기사는 인터넷의 다양한 출처에서 편집되었습니다. 이 기사가 유용했기를 바랍니다. 이 기사가 유용하다고 생각되면 공유하십시오. 매우 감사합니다!
사람들이 주제에 대해 자주 검색하는 키워드 3 46 Su dung Object browser de tra cuu trong VBA Su dung Object browser de tra cuu trong VBA
- # Học lập trình – YouBo
- # Tự học lập trình
3 #46 # #Su #dung #Object #browser #de #tra #cuu #trong #VBA # #Su #dung #Object #browser #de #tra #cuu #trong #VBA
YouTube에서 enq ro fast object reuse 주제의 다른 동영상 보기
주제에 대한 기사를 시청해 주셔서 감사합니다 3 46 Su dung Object browser de tra cuu trong VBA Su dung Object browser de tra cuu trong VBA | enq ro fast object reuse, 이 기사가 유용하다고 생각되면 공유하십시오, 매우 감사합니다.
