Wait event in 10g "events in waitclass others" , DB is stuck

Hi ,
I need help ,
no one can login into the DB , there are 5 updates running in parallel right now ,
only those who were inside before the updates began to run can work .
connect through listener is impossible , but without listener (i.e sqlplus user/password) is o.k .
in v$session_event for each update I see "events in waitclass others" wait event , with large values either in "total_waits" column , and "total_timeouts" .
I cannot find anything in asktom , or google .
yesterday we migrated from 9i to 10g .
a month ago we did the same in the dev area with no problems .
did anyone see that events before , and know what should be done to solve this problem ?
Thanks ,
Lior .

sir,
my few parameters that i've set.
fast_start_mttr_target = 220
db_recovery_file_dest_size = 10G (includes backupset, archivelogs, flashback)
sga_target = 1048M
pga_aggregate_target = 600M
these two statements consuming significant time of wait..
SELECT TO_CHAR(OLDEST_FLASHBACK_TIME, 'YYYY-MM-DD HH24:MI:SS') FROM V$FLASHBACK_DATABASE_LOG
SELECT (:"SYS_B_0" - sum(percent_space_used)) + sum(percent_space_reclaimable)
FROM v$flash_recovery_area_usage
there is also lots of time consuming in control file sequential read..
any hints for the problem..which parameters i've to check or any other...

Similar Messages

What is "KJC: Wait for msg .." wait event in 10g??

Hi, all.
The database is 2 node RAC database (10.2.0.2.0)
on 32-bit windows 2003 EE SP1.
I found "KJC: Wait for msg sends to complete" wait event in
"Top 5 Timed Event" Section from AWR report.
What is "KJC: Wait for msg sends to complete" wait event??
The following is from UDUMP.
Dump file d:\oracle\product\10.2.0\admin\rac\udump\rac2_ora_5656.trc
Mon Sep 24 00:04:40 2007
ORACLE V10.2.0.2.0 - Production vsnsta=0
vsnsql=14 vsnxtr=3
Oracle Database 10g Enterprise Edition Release 10.2.0.2.0 - Production
With the Real Application Clusters, OLAP and Data Mining options
Windows Server 2003 Version V5.2 Service Pack 1
CPU : 4 - type 586, 2 Physical Cores
Process Affinity : 0x00000000
Memory (Avail/Total): Ph:5278M/8190M, Ph+PgF:6596M/10041M, VA:316M/2047M
Instance name: rac2
Redo thread mounted by this instance: 2
Oracle process number: 64
Windows thread id: 5656, image: ORACLE.EXE (SHAD)
*** 2007-09-24 00:04:40.156
*** ACTION NAME:() 2007-09-24 00:04:40.156
*** MODULE NAME:(OEM.SystemPool) 2007-09-24 00:04:40.156
*** SERVICE NAME:(RAC.world) 2007-09-24 00:04:40.156
*** CLIENT ID:() 2007-09-24 00:04:40.156
*** SESSION ID:(486.53) 2007-09-24 00:04:40.156
IPCSendMsg: could not initiate send on conn 0x5b0d3e98 to node [rac1 : 696 : 3996 : 359937], err 10054
IPCGetRequestInfo: failed a request rqh(0x5b060db8), type(6), status(2), bytes(0)
Thanks and Regards.
Message was edited by:
user507290
Message was edited by:
user507290

This might have something to do with bug 5075434 - Small performance overhead in RAC (waits for "KJC: Wait for msg sends to complete").
Check metalink for further details.

Read by other session wait event

I have some reports in my database that whenever executed by two or more session these reports suffers with read by other session wait event. Tables which are involving in that's query i moves them to other tablespace and then move back to original tablespace. Some how this could solves read by other session wait event. But after some days these problem occur again.
How can i permanently solve this problem??
My db is Oracle Database 10g Enterprise Edition Release 10.2.0.3.0 - Prod
Oracle Block size 4096
Thanks

Hi there,
Searching for this wait eventin the docs gave this,
http://download.oracle.com/docs/cd/B19306_01/server.102/b14237/waitevents003.htm#sthref3159
read by other session
This event occurs when a session requests a buffer that is currently being read into the buffer cache by another session. Prior to release 10.1, waits for this event were grouped with the other reasons for waiting for buffers under the 'buffer busy wait' event
Wait Time: Time waited for the buffer to be read by the other session (in microseconds)And a quick google search for the same gave these results in the top.
http://www.confio.com/English/Tips/Read_By_Other_Session.php
http://www.dbafan.com/blog/?p=132
HTH
Aman....

What is "reliable message" wait event in 10g??

Hi, all.
The database is 2 node RAC 10.2.0.2.0 on 32-bit windows 2003 EE SP1.
From time to time, I see "reliable message" wait event on the
"Top 5 Timed Events" section from AWR report.
The wait class is "Other".
There seems to be no manuals and html links explaining "reliable message"
wait event.
Thanks and Regards.
Message was edited by:
user507290
Message was edited by:
user507290

Metalink Doc 461052.1 is a fairly lightweight walk-through of a system resource profiling tool called LTOM, the "Lite Onboard Monitor". It has an appendix in which it simply points out "The following events were considered idle and ignored... reliable message..."
It also says that if you want to include something for wait analysis, just take it out of the list of idle and ignored events... so it's not exactly saying that the thing is an idle event, just that it was treated as such for the purposes of writing that document but that you might think differently.
On the other hand, this page:
http://download.oracle.com/docs/cd/B19306_01/server.102/b14237/waitevents003.htm
...is 10g Release 2's description of "wait events of greatest interest"... and "reliable message" isn't on it! From which one concludes, I suppose, that it isn't of great interest!

Streams AQ wait event on Oracle 10g

Hello,
I have ECC 6.0 on W2k3 with Oracle. I have some wait event about Streams AQ :
Streams AQ: waiting for messages in the queue
Streams AQ: qmn slave idle wait
Streams AQ: qmn coordinator waiting for slave to start
What does it mean ? What can I do to fix that?
From what I read, it's seems to have something to do with parameter : aq_tm_processes
What this parameter whould be set to? It seems to be set to O now.
Thank you for any help,
Nicholas

Hi,
What is the Patch Level of Oracle 10g which is in use ?
Please refer Oracle Meta link 428441.1 to get more information. It will tell you the reason and the possible alternatives to deal with it. You can refer SAP Note 758563 to get Oracle Meta link access.
Unless you use Oracle Streams Advanced Queuing , there's no need to set this parameter.
If AQ_TM_PROCESSES is not specified or is set to 0, then the queue monitor is not created.
In 10gR2 parameter AQ_TM_PROCESSES shouldn't be set explicitly in pfile/spfile, because Oracle autotunes it.
Also refer the [this link|SRM Alert Management does not determine recipient runtime?; to get more info.
Regards,
Bhavik G. Shroff

How to see the wait events info. after excute a select query

Hi
How to see the wait events info. after execute a select query. Are there any parameter to set for this option?
And also wanna see the follwing info. in trace file. For this what are the parameters I have to set right?
SELECT * FROM emp, dept
WHERE emp.deptno = dept.deptno;
call   count      cpu    elapsed     disk    query current    rows
Parse      1     0.16      0.29         3       13       0       0
Execute    1     0.00      0.00         0        0       0       0
Fetch      1     0.03      0.26         2        2       4      14
Misses in library cache during parse: 1
Parsing user id: (8) SCOTT Regards
Arpitha

$ sqlplus scott/tiger
SQL*Plus: Release 10.2.0.2.0 - Production on Wed Apr 20 15:29:33 2011
Copyright (c) 1982, 2005, Oracle. All Rights Reserved.
Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.2.0 - Production
With the Partitioning, OLAP and Data Mining options
SQL> SHOW PARAMETER dump
NAME                                 TYPE        VALUE
background_core_dump                 string      partial
background_dump_dest                 string      /user/oracle/app/oracle/admin/
                                                 orclsb/bdump
core_dump_dest                       string      /user/oracle/app/oracle/admin/
                                                 orclsb/cdump
max_dump_file_size                   string      UNLIMITED
shadow_core_dump                     string      partial
user_dump_dest                       string      /user/oracle/app/oracle/admin/
                                                 orclsb/udump
SQL> ALTER SESSION SET EVENTS='10046 trace name context forever, level 12';
Session altered.
SQL> SELECT * FROM emp WHERE deptno=20;
     EMPNO ENAME      JOB              MGR HIREDATE         SAL       COMM
    DEPTNO
      7369 SMITH      CLERK           7902 17-DEC-80        800
        20
      7566 JONES      MANAGER         7839 02-APR-81       2975
        20
      7788 SCOTT      ANALYST         7566 19-APR-87       3000
        20
     EMPNO ENAME      JOB              MGR HIREDATE         SAL       COMM
    DEPTNO
      7876 ADAMS      CLERK           7788 23-MAY-87       1100
        20
      7902 FORD       ANALYST         7566 03-DEC-81       3000
        20Now
$ pwd
/user/oracle/app/oracle/admin/orclsb/udump
$ ls -ltr|tail -5
-rw-r-----   1 oracle   oinstall     622 Apr 20 11:35 orclsb_ora_949.trc
-rw-r-----   1 oracle   oinstall     651 Apr 20 11:35 orclsb_ora_976.trc
-rw-r-----   1 oracle   oinstall    1982 Apr 20 11:35 orclsb_ora_977.trc
-rw-r-----   1 oracle   oinstall    1443 Apr 20 15:29 orclsb_ora_1251.trc
-rw-r-----   1 oracle   oinstall 279719 Apr 20 15:30 orclsb_ora_1255.trc
$ tkprof orclsb_ora_1255.trc orclsb_ora_1255.txt
TKPROF: Release 10.2.0.2.0 - Production on Wed Apr 20 15:32:17 2011
Copyright (c) 1982, 2005, Oracle. All rights reserved.
$ ls -ltr|tail -5
-rw-r-----   1 oracle   oinstall     651 Apr 20 11:35 orclsb_ora_976.trc
-rw-r-----   1 oracle   oinstall    1982 Apr 20 11:35 orclsb_ora_977.trc
-rw-r-----   1 oracle   oinstall    1443 Apr 20 15:29 orclsb_ora_1251.trc
-rw-r-----   1 oracle   oinstall 279719 Apr 20 15:30 orclsb_ora_1255.trc
-rw-r--r--   1 oracle   oinstall   26872 Apr 20 15:32 orclsb_ora_1255.txtThis orclsb_ora_1255.txt contains the required information.

Hash join ending up in huge wait events

Hi,
We are experiencing huge wait events ( direct path read temp , direct path write temp) on our Materialized View refresh in 10.2.0.4 version of oracle 10g in linux rhel5 environment while monitoring the refresh session from db console. While checking the explain plan of the mv query there is a huge hash_join (due to self join nature of the query) is shown. As advised in some dba forums, i have increased my pga_aggregate_target to a value of 4 gb from 1800 mb. The PGA_HIT % is raised to 60% from 58% ( just 2% improvement). But still my direct path read temp and direct path write temp wait event have not reduced and a huge temp space is taken for hash join.
Since we have some usage limit set by some hidden parameters for a each session on pga_aggregate_target, increase the size did not helped me much. The mv refresh is taking more than 5 hours ( sometimes it exceeds 5 hrs) to completes it refresh where as the same query in window (production) is completed less than two hours. Before a month, the refresh time in both environment was nearly close. But now it has changed and not able to figure it out.
STATISTICS have been collected regularly using dbms_gather_stats in both environment. Both mv refresh are scheduled to run using dbms_scheduler (Manual refresh). SGA_TARGET and other memory parameters are almost same.
Environment : Dataware house
O/s : RHEL 5
Oracle version : 10.2.0.4
Work_policy=auto
Is there any possibility to reduce this wait event and there by reducing the elapsed time? I am also interested to know changing the plan to use other sort will help? I don't know whether the details are sufficient to analyze this issue. If you need more details on this just let me know.
I really appreciate your help and thanks in advance to all.

Thans for your comments. Here is the code, explan plan and autotrace trace stat output.
SELECT lasg.employee_number "EMPLOYEE_NUM",
lasg.full_name "FULL_NAME",
lasg.person_id "PERSON_ID",
SUBSTR (lasg.organization, 1, 4) "DEPT",
casg.assign_start_date "EFFECTIVE_START_DATE",
casg.assign_end_date "EFFECTIVE_END_DATE",
hasg.organization "PRIOR_ORG",
casg.organization organization,
hasg.supervisor "PRIOR_SUPERVISOR",
casg.supervisor "SUPERVISOR_NAME",
hasg.location "PRIOR_LOCATION",
casg.location location,
hasg.job_title "PRIOR_TITLE",
casg.job_title job_name,
CASE
WHEN hasg.organization = casg.organization THEN 'No Change'
ELSE 'Change'
END
org_change,
CASE
WHEN hasg.location = casg.location THEN 'No Change'
ELSE 'Change'
END
loc_change,
CASE
WHEN hasg.supervisor = casg.supervisor THEN 'No Change'
ELSE 'Change'
END
sup_change,
CASE
WHEN hasg.job_title = casg.job_title THEN 'No Change'
ELSE 'Change'
END
job_change
FROM panad.data_employ_details lasg,
panad.data_employ_details casg,
panad.data_employ_details hasg
WHERE lasg.person_id = casg.person_id(+)
AND lasg.assign_end_date = (SELECT MAX (lasg2.assign_end_date)
FROM panad.data_employ_details lasg2
WHERE lasg.person_id = lasg2.person_id)
AND casg.person_id = hasg.person_id(+)
AND hasg.assign_start_date =
(SELECT MAX (hasg2.assign_start_date)
FROM panad.data_employ_details hasg2
WHERE hasg2.person_id = lasg.person_id
AND hasg2.assign_end_date < casg.assign_start_date)
| Id | Operation                 | Name                       | Rows | Bytes |TempSpc| Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT          |                            |     1 |   303 |       | 10261 (91)| 00:02:04 |
|* 1 | FILTER                   |                            |       |       |       |            |          |
|* 2 |   HASH JOIN               |                            |     1 |   303 |       | 10179 (91)| 00:02:03 |
|* 3 |    HASH JOIN              |                            |     5 | 1060 |       | 10095 (92)| 00:02:02 |
|* 4 |     HASH JOIN             |                            | 6786 |   960K|       | 10011 (93)| 00:02:01 |
|   5 |      VIEW                 | VW_SQ_1                    | 6786 |   225K|       | 9927 (94)| 00:02:00 |
|   6 |       HASH GROUP BY       |                            | 6786 |   384K|       | 9927 (94)| 00:02:00 |
|   7 |        MERGE JOIN         |                            |    50M| 2820M|       | 1427 (53)| 00:00:18 |
|   8 |         SORT JOIN         |                            | 31937 |   998K| 2776K|   367   (2)| 00:00:05 |
|   9 |          TABLE ACCESS FULL| DATA_EMPLOY_DETAILS            | 31937 |   998K|       |    82   (2)| 00:00:01 |
|* 10 |         SORT JOIN         |                            | 31937 |   810K| 2520K|   324   (2)| 00:00:04 |
| 11 |          TABLE ACCESS FULL| DATA_EMPLOY_DETAILS        | 31937 |   810K|       |    82   (2)| 00:00:01 |
| 12 |      TABLE ACCESS FULL    | DATA_EMPLOY_DETAILS        | 31937 | 3461K|       |    83   (3)| 00:00:01 |
| 13 |     TABLE ACCESS FULL     | DATA_EMPLOY_DETAILS        | 31937 | 2089K|       |    83   (3)| 00:00:01 |
| 14 |    TABLE ACCESS FULL      | DATA_EMPLOY_DETAILS        | 31937 | 2838K|       |    83   (3)| 00:00:01 |
| 15 |   SORT AGGREGATE          |                            |     1 |    13 |       |            |          |
|* 16 |    TABLE ACCESS FULL      | DATA_EMPLOY_DETAILS        |     5 |    65 |       |    82   (2)| 00:00:01 |
Predicate Information (identified by operation id):
   1 - filter("LASG"."ASSIGN_END_DATE"= (SELECT MAX("LASG2"."ASSIGN_END_DATE") FROM
              "PANAD"."DATA_EMPLOY_DETAILS" "LASG2" WHERE "LASG2"."PERSON_ID"=:B1))
   2 - access("CASG"."PERSON_ID"="HASG"."PERSON_ID" AND "HASG"."ASSIGN_START_DATE"="VW_COL_1")
   3 - access("LASG"."PERSON_ID"="CASG"."PERSON_ID" AND "PERSON_ID"="LASG"."PERSON_ID")
   4 - access("ROWID"=ROWID)
10 - access(INTERNAL_FUNCTION("HASG2"."ASSIGN_END_DATE")<INTERNAL_FUNCTION("CASG"."ASSIGN_START_DATE")
       filter(INTERNAL_FUNCTION("HASG2"."ASSIGN_END_DATE")<INTERNAL_FUNCTION("CASG"."ASSIGN_START_DATE")
16 - filter("LASG2"."PERSON_ID"=:B1)
37 rows selected.
- autot trace stat output -
5070 rows selected.
Statistics
      35203 recursive calls
          0 db block gets
    3675913 consistent gets
    4269882 physical reads
          0 redo size
    1046781 bytes sent via SQL*Net to client
       4107 bytes received via SQL*Net from client
        339 SQL*Net roundtrips to/from client
         69 sorts (memory)
          0 sorts (disk)
       5070 rows processed   I have tried running this query with paralell but not helped.
I have read the links provided by both of you. Dictionary and fixed table stats are collected as a routine.
From the link given byTaral, Greg Rahn has suggested that it is a bug as below.
Its bug 9041800 and there is a 10.2.0.4 backport available as of 01/29/10.How can i get this bug fixed since there is no explanation of what need to be done? Do i need to contact oracle support for the 10.2.0.4 backport for RHEL5?
Thanks in advance
Edited by: Karthikambalav on Mar 9, 2010 2:43 AM

Tuning row lock contention wait events

Hello everyone,
Working on 10g/windows
Top 5 events
EVENT TOTAL_WAITS TIME_WAITED AVG_MS PERCENT
CPU 9462339 48
enq: TX - row lock contention 12531 3660728 2921.34 18
control file parallel write 1300731 3088079 23.74 16
log file parallel write 1510503 1264080 8.37 6
log file sync 1072553 968007 9.03 5
Distribution of row lock wait during the last 4 days in the database server
END_INTERVAL_TIME TOTAL_WAITS TIME_WAITED_MICRO AVG_WAIT_MS
2008-04-01 16:00:58 909 2721008230 2993.41
2008-04-01 15:00:27 50 149941140 2998.82
2008-03-31 12:00:42 193 575595397 2982.36
2008-03-29 23:00:13 172 513058700 2982.9
2008-03-29 22:00:37 164 483940046 2950.85
2008-03-27 22:00:35 565 1667120838 2950.66
2008-03-26 18:00:59 348 1042918982 2996.89
My analysis:
It's obvious that the row lock contention wait time is huge, and this direct me to find out SQL stmt, causing this.
all the SQL statement was SELECT ....... FOR UPDATE stmt.
I was also able to find out locked tables.
My tuning idea:
1. I'm thinking to reorganize hot tables as well as their indexes, but by instinct it seems to not give so much value to avoid the huge row lock wait time.
2. I'm also seeing if I can reduce the number of rows per block, by increasing PCTFREE and diminishing PCTUSED, so the contention will spread over many blocks instead of one heavy block.
Question
As SQL stmt related to those locked tables are select ... for update, how could I tune this kind of stmt?
Does someone have other idea to come up with this row lock contention?
Tanks for your effort and help

Taking another look at your suggested function based index, it depends on the data type of the DEV.POS_FOLIO_ID.POS_FOLIO_ID column. If the column is defined as a number, and it is a primary key, there will already be a usable index on that column.
Yesterday, I wrote this: "Once I understood why or how the sessions were trying to insert duplicate primary key values, I would try to determine why the average number of seconds for the wait event is almost 3 seconds (maybe a timeout)."
After fixing the formatting of the top 5 wait events (total duration unknown):
EVENT                        TOTAL_WAITS TIME_WAITED   AVG_MS PERCENT
CPU                                         94,623.39             48
enq: TX - row lock contention     12,531    36,607.28 2921.34    18
control file parallel write    1,300,731    30,880.79    23.74    16
log file parallel write        1,510,503    12,640.80     8.37     6
log file sync                  1,072,553     9,680.07     9.03     512,531 * 3 second time out = 37,593 seconds = 10.44 hours.
What if the reason for the 3 second average wait time is due to a timeout. I performed a little experiment... I changed a row in a test table and then made a pot of coffee.
In session 1:
CREATE TABLE T1 (
C1 NUMBER(10),
C2 NUMBER(10),
PRIMARY KEY (C1));
INSERT INTO T1
SELECT
ROWNUM,
ROWNUM*10
FROM
DUAL
CONNECT BY
LEVEL<=1000000;
COMMIT;I now have a test table with 1,000,000 rows. I start monitoring the changes in the wait events roughly every 60 seconds, and V$SESSION_WAIT and V$LOCK roughly 4 times per second.
Back in session 1:
UPDATE
T1
SET
C1=-C1
WHERE
C1<=100;I have now modified the first 100 rows that were inserted into the table, time to make the pot of coffee.
In session 2, I try to insert a row with a primary key value of -10:
INSERT INTO T1 VALUES (
-10,
10);Session 2 hangs.
If I take the third 60 second snap of the system wide wait events as the zero point, and the 11th snap as the end point. There were 149 waits on ENQ: TX - ROW LOCK CONTENTION, 148 time outs, 446.62 seconds of total time in the wait event, with an average wait time of 2.997450 seconds.
Rolling down to the session level wait events, SID 208 (my session 2) had 149 waits on ENQ: TX - ROW LOCK CONTENTION, for a total time of 446.61 seconds with an average wait time of 2.997383 seconds. All of the 149 waits and the wait time was in this one session that was locked up for the full duration of this time period because session 1 was making a pot of coffee.
Rolling down to V$SESSION_WAIT (sampled roughly 4 times per second): At the start of the third time interval, SID 208 has been in the ENQ: TX - ROW LOCK CONTENTION wait event for 39 seconds and is actively waiting trying to execute SQL with a hash value of 1001532423, the wait object is -1, wait file is 0, wait block is 0, wait row is 0, P1 is 1415053316, P2 is 196646, P3 is 4754.
At the end of the 11th time interval: , SID 208 has been in the ENQ: TX - ROW LOCK CONTENTION wait event for 483 seconds and is actively waiting trying to execute SQL with a hash value of 1001532423, the wait object is -1, wait file is 0, wait block is 0, wait row is 0, P1 is 1415053316, P2 is 196646, P3 is 4754.
Rolling down to V$LOCK (sampled roughly 4 times per second): I see that SID 214 (session 1) is blocking SID 208 (session 2). SID 214 has a TX lock in mode 6 with ID1 of 196646 and ID2 of 4754. SID 208 is requesting a TX lock in mode 4 with ID1 of 196646 and ID2 of 4754.
So, it seems that I need a faster coffee pot rather than an additional index on my table. It could be that the above process would have found that the application associated with SID 214 was abandoned or crashed and for some reason the lock was not released for a long period of time, a little less than 10.44 hours in your case.
Charles Hooper
IT Manager/Oracle DBA
K&M Machine-Fabricating, Inc.

10.2.0.3 high concurrency wait event

I have a new 64bit windows 10g 10.2.0.3 VM server doing nothing but spinning its wheels. I intalled Oracle on it Friday and when I checked it tonight I see it is getting high concurrency wait events. Looks like every 10 minutes concurrency goes up to about 35.0 (?seconds) and then goes back to 0 - up and down every few minutes. Just enough to hit the warning threashold.
I need this machine for a peoplesoft install on Monday morning.
Anyone have any ideas what this could be? I kinda know what concurrency is but not sure if it could be from hardware or software.
Didn't see any patches/bugs but I will continue to look.
Help, Kathie

What are the wait events as described in v$system_wait and v$session_event?

RE: Looking for some database statistics and wait event statistics

Hi:
We are using Oracle 10g RAC on Sun Solaris 5.9.
1) In GV$SYSSTAT, we cannot find the following database statistics:
     'global cache converts',
     'global cache convert time',
     'global cache gets',
     'global cache get time',
     'global cache convert timeouts',
     'global cache defers'
2) In GV$SYSTEM_EVENT, we cannot find the following wait event:
     'buffer busy global CR'
For 1) and 2), could you please tell us where to retrieve the above information,
or suggest a reasonable alternative?
Have these stats been removed in Oracle 10g?
Have they been renamed? To what?
3) We currently compute the number of additional redo logs that can be accommodated in the free space of the archive directory using the formula:
(arhive directory free space / redo log file size)
However, using ASM we find that the free space for a ASM diskgroup is being reported as zero in the table v$asm_diskgroup if the diskgroup is mounted manually. How would one go about retrieving the free space for a logical volume?
Thanks

Hi:
We are using Oracle 10g RAC on Sun Solaris 5.9.
1) In GV$SYSSTAT, we cannot find the following database statistics:
     'global cache converts',
     'global cache convert time',
     'global cache gets',
     'global cache get time',
     'global cache convert timeouts',
     'global cache defers'
2) In GV$SYSTEM_EVENT, we cannot find the following wait event:
     'buffer busy global CR'
For 1) and 2), could you please tell us where to retrieve the above information,
or suggest a reasonable alternative?
Have these stats been removed in Oracle 10g?
Have they been renamed? To what?
3) We currently compute the number of additional redo logs that can be accommodated in the free space of the archive directory using the formula:
(arhive directory free space / redo log file size)
However, using ASM we find that the free space for a ASM diskgroup is being reported as zero in the table v$asm_diskgroup if the diskgroup is mounted manually. How would one go about retrieving the free space for a logical volume?
Thanks

100% CPU, wait event : latch shared pool

I have a store procedure, run in one of database, it hangs in a "create table ... as select ..." statement.
the wait event is : latch shared pool, and CPU is up to 100%, it has run over few hours and seems hang.
Same stored procedure run on others enviroment, never seen such problem, even run on the same data size or even much much bigger data size.
This procedure has been used more than 2 years, never see such problem in any others enviroment. it only happend in this new setup enviroment.
however, in this enviroment, if I try to reduce data to be very very small, I was able to see procudure complate in 10 sec.
I suspect parameter, for example, I changed shared_pool_size from 40MB to 150 MB, re-start database and re-run, still see the same problem here.
Could anybody suggest any thing I can look into?
Thanks

jjzz wrote:
I have a store procedure, run in one of database, it hangs in a "create table ... as select ..." statement.
the wait event is : latch shared pool, and CPU is up to 100%, it has run over few hours and seems hang.
If it's running at 100% CPU, it's not waiting.
Does v$session_wait (or even v$session since you seem to be running 10g) tell you that the session is *"waiting"*, or is it simply noting that your last wait was on the shared pool latch ?
If the latter, then you probably have some SQL in the procedure that has changed its execution plan to become much more CPU intensive - perhaps because of a small change in the data volume, data distribution, or statistics.
First step - find out what SQL statements are executing, and see how much work they are doing. You could query v$session for that session a few times and check what the sql_id and sql_child number are, also prev_sql_id and prev_child_number. If these stay constant, one or other may give you the guilty SQL statement. If not check v$open_cursor for the session.
Regards
Jonathan Lewis
http://jonathanlewis.wordpress.com
http://www.jlcomp.demon.co.uk
"Science is more than a body of knowledge; it is a way of thinking"
Carl Sagan

Library cache lock wait event

Hi,
I am experience hanging in my database. I am using 10.2.0.3 on Solaris 5.10.
I am having automatic processes that drop the schema and recreate the schema and upload the new data. Since the last few days i am facing in hanging while dropping the schema. I checked and found "Library cache lock" event that caused other processes also in the hanged state. I am trying to find out the reason but not able to crack.
Can some one advice me?
Thanks

Hi,
There exists an concurrency problem with respect to the object - resource utilization.
- One client can prevent other clients from accessing the same object
- The client can maintain a dependency for a long time (for example, no other client can change the object)
check the from v$session_wait (query taken from the http://www.dba-oracle.com/m_library_cache_pin.htm - for your reference)
select decode(lob.kglobtyp, 0, 'NEXT OBJECT', 1, 'INDEX', 2, 'TABLE', 3, 'CLUSTER',
4, 'VIEW', 5, 'SYNONYM', 6, 'SEQUENCE',
7, 'PROCEDURE', 8, 'FUNCTION', 9, 'PACKAGE',
11, 'PACKAGE BODY', 12, 'TRIGGER',
13, 'TYPE', 14, 'TYPE BODY',
19, 'TABLE PARTITION', 20, 'INDEX PARTITION', 21, 'LOB',
22, 'LIBRARY', 23, 'DIRECTORY', 24, 'QUEUE',
28, 'JAVA SOURCE', 29, 'JAVA CLASS', 30, 'JAVA RESOURCE',
32, 'INDEXTYPE', 33, 'OPERATOR',
34, 'TABLE SUBPARTITION', 35, 'INDEX SUBPARTITION',
40, 'LOB PARTITION', 41, 'LOB SUBPARTITION',
42, 'MATERIALIZED VIEW',
43, 'DIMENSION',
44, 'CONTEXT', 46, 'RULE SET', 47, 'RESOURCE PLAN',
48, 'CONSUMER GROUP',
51, 'SUBSCRIPTION', 52, 'LOCATION',
55, 'XML SCHEMA', 56, 'JAVA DATA',
57, 'SECURITY PROFILE', 59, 'RULE',
62, 'EVALUATION CONTEXT',
'UNDEFINED') object_type,
lob.KGLNAOBJ object_name,
pn.KGLPNMOD lock_mode_held,
pn.KGLPNREQ lock_mode_requested,
ses.sid,
ses.serial#,
ses.username
FROM
x$kglpn pn,
v$session ses,
x$kglob lob,
v$session_wait vsw
WHERE
pn.KGLPNUSE = ses.saddr and
pn.KGLPNHDL = lob.KGLHDADR
and lob.kglhdadr = vsw.p1raw
and vsw.event = 'library cache pin'
order by lock_mode_held desc
Resolution might - you need to check the time it takes (the script to drop the schema) and it loads - either doing from parallel sessions or in serial order. I doubt it, till the schema get dropped completely it should not be accessible to any other applications - either objects too, that makes the rise to concurrency Issue with respect to library cache waits - the other sessions are trying access the object.
- Pavan Kumar N
- ORACLE 9i/10g - OCP
http://www.oracleinternals.blogspot.com

What is ges reusing os pid wait event

What is wait event "ges reusing os pid". In our RAC environment it is one of the top wait events. How to minimze it.

This is a wait event in Oracle 10g for Global Enqueue Services (ges) waiting on an operating system process id (os pid).
How to resolve this issue? I checked the bug list on Metalink and there is a patch set for the issue that may help.
Question: what version and patch release are you running for Oracle RAC?
Also, you probably want to tune your public network and private interconnects between the nodes in your Oracle RAC cluster.
Regards,
Ben Prusinski
http://oracle-magician.blogspot.com/

Wait events and locks monitoring /resolving scripts

Looking for wait events and locks monitoring /resolving scripts /tips.

Hi,
Looking for wait events and locks monitoring /resolving scriptsHere is the collection of monitoring scripts that I
use, and it has dozens of scripts for locking:
http://www.oracle-script.com
For one-off scripts, here is a script by Laurent Baylac to show locks in Oracle 10g:
http://www.dba-village.com/village/dvp_scripts.ScriptDetails?ScriptIdA=3508
SET LINESIZE 500
SET PAGESIZE 1000
COLUMN username FORMAT A15
COLUMN machine FORMAT A25
COLUMN logon_time FORMAT A20
SELECT LPAD(' ', (level-1)*2, ' ') || NVL(s.username, '(oracle)') AS username,
s.osuser,
s.sid,
s.serial#,
s.lockwait,
s.status,
s.module,
s.machine,
s.program,
TO_CHAR(s.logon_Time,'DD-MON-YYYY HH24:MI:SS') AS logon_time
FROM v$session s
CONNECT BY PRIOR s.sid = s.blocking_session
START WITH s.blocking_session IS NULL;
SET PAGESIZE 14
-- Search for locked objects
-- To be executed under the SYSTEM account
-- Compatible with Oracle10.1.x and higher
select
distinct to_name object_locked
from
v$object_dependency
where
to_address in
select /*+ ordered */
w.kgllkhdl address
from
dba_kgllock w,
dba_kgllock h,
v$session w1,
v$session h1
where
(((h.kgllkmod != 0) and (h.kgllkmod != 1)
and ((h.kgllkreq = 0) or (h.kgllkreq = 1)))
and
(((w.kgllkmod = 0) or (w.kgllkmod= 1))
and ((w.kgllkreq != 0) and (w.kgllkreq != 1))))
and w.kgllktype = h.kgllktype
and w.kgllkhdl = h.kgllkhdl
and w.kgllkuse = w1.saddr
and h.kgllkuse = h1.saddr
Don Burleson
Oracle Press author

Buffer Exterminate Wait Event

Hello Experts,
In our database (10g/Solaris 9) the major wait event is "Buffer Exterminate". Ours is an OLTP database. We have set Auto SGA. As per metalink this wait event happens when Oracle tries to pull memory out of some pool and allocates it to something else. Even after increasing SGA_TARGET we are unable to get rid of it.
Can you please describe how to reduce this wait event? Should we go for manual SGA?
Regards,
Deepak

do you have oracle support and metalink access, if yes as mentioned in the link there are notes related to this wait and if they do not help you you may open a service request of course - https://metalink.oracle.com/metalink/plsql/f?p=130:14:10666479452361189216::::p14_database_id,p14_docid,p14_show_header,p14_show_help,p14_black_frame,p14_font:NOT,259137.1,1,1,1,helvetica
https://metalink.oracle.com/metalink/plsql/f?p=130:14:10666479452361189216::::p14_database_id,p14_docid,p14_show_header,p14_show_help,p14_black_frame,p14_font:NOT,429390.1,1,1,1,helvetica
best regards.

Wait event in 10g "events in waitclass others" , DB is stuck

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