Database Wait time calculation.

Hi i am using 10.2.0.4.0 version of oracle.
I need to find the total wait times for each days for each WAIT_CLASS and need to plot the trends in past days. i am using below query for getting the details, but my results are not matching with the ones i am getting in the AWR report. In my daily AWR report, 'USER I/O' is coming at highest time taking wait class, where as in my query i am getting 'Application' on highest wait section. Also the total wait times comes different. Can you please help me to understand, what am i missing in the query?
SELECT wait_class,
     TO_CHAR (MIN (s.end_interval_time), 'DD-MON-YYYY DY HH24:MI')
         sample_end,
        SUM (WAIT_TIME + time_waited) waittime
FROM dba_hist_active_sess_history q, dba_hist_snapshot s
WHERE   s.snap_id = q.snap_id
      AND s.dbid = q.dbid
      AND s.instance_number = q.instance_number
      AND s.end_interval_time >=
             TO_DATE (TRIM ('16-Oct-2012 '), 'dd-mon-yyyy hh24:mi:ss')
      AND s.begin_interval_time <=
             TO_DATE (TRIM ('18-nov-2012 '), 'dd-mon-yyyy hh24:mi:ss')
     AND wait_class in ('User I/O','System I/O','Concurrency','Commit','Other','Configuration','Network','Application','Administrative')
GROUP BY trunc(s.end_interval_time),wait_class
ORDER BY trunc(s.end_interval_time),waittime desc

Thanks. I executed the below query and got the results for the same duration as in my AWR report, i.e '02-Nov-12 00:10:14' to '02-Nov-12 16:50:40' but i am wondering the trend of wait times as per each class are comparably similar but nos i.e. SUM(time_waited) are different in both the cases(AWR and below QUERY), they are not exact match. Why am i getting this difference?
SELECT wait_class,
       --TO_CHAR (MIN (s.end_interval_time), 'DD-MON-YYYY DY HH24:MI'),
       trunc(s.end_interval_time),
        SUM(time_waited)
FROM   dba_hist_service_wait_class dhswc
       , dba_hist_snapshot s
where    S.SNAP_ID = dhswc.snap_id
AND wait_class in ('User I/O','System I/O','Concurrency','Commit','Other','Configuration','Network','Application','Administrative')
AND s.end_interval_time >=
             TO_DATE (TRIM ('02-Nov-12 00:10:14'), 'dd-mon-yyyy hh24:mi')
      AND s.begin_interval_time <=
             TO_DATE (TRIM ('02-Nov-12 16:50:40'), 'dd-mon-yyyy hh24:mi')
GROUP BY Trunc(end_interval_time),
          wait_class
ORDER BY Trunc(end_interval_time),
          wait_class;Edited by: 930254 on Nov 8, 2012 8:01 AM
Edited by: 930254 on Nov 8, 2012 8:05 AM

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Message was edited by:
millerand

Please try the following code in your doClosure method. Replace your code with the following code.
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Hi Friends,
Please answer my queries below.
Thanks and Regards
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Hi,
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CEO: What exactly is stopping us from doing this?
Expert: Geometry
Marketing Manager: Just ignore it.
Attachments:
TimingVI_Behavior_2011.vi ‏29 KB

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Dear,
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Regards

Java.sql.SQLException: No available resource. Wait-time expired.

Hi all,
The application platform is SunONE Application Server 7, and the database is ORACLE 9i. My Website application will raise the SQLException once a few days' running. Everything will be ok once the Application server has been restarted. The detail about the Exception is :
[12/Aug/2003:10:41:03] WARNING (25931): CORE3283: stderr: java.sql.SQLException: No available resource. Wait-time expired.
[12/Aug/2003:10:41:03] WARNING (25931): CORE3283: stderr:      at com.sun.enterprise.resource.JdbcDataSource.internalGetConnection(JdbcDataSource.java:251)
[12/Aug/2003:10:41:03] WARNING (25931): CORE3283: stderr:      at com.sun.enterprise.resource.JdbcDataSource.getConnection(JdbcDataSource.java:98)
[12/Aug/2003:10:41:03] WARNING (25931): CORE3283: stderr:      at com.tsp.gdgpo.ejbm.util.EnvUtil.getDSConnection(EnvUtil.java:72)
[12/Aug/2003:10:41:03] WARNING (25931): CORE3283: stderr:      at com.tsp.gdgpo.ejbm.util.DirectDSUtil.getObjectsFromDS(DirectDSUtil.java:103)
[12/Aug/2003:10:41:03] WARNING (25931): CORE3283: stderr:      at com.tsp.gdgpo.ejbm.jcsms.dam.JcsmsDDSA.getSpecialistByPage(JcsmsDDSA.java:388)
[12/Aug/2003:10:41:03] WARNING (25931): CORE3283: stderr:      at com.tsp.gdgpo.ejbm.jcsms.sessionbeans.SpecialManagerEJBBean.listSpecialist(SpecialManagerEJBBean.java:1941)
[12/Aug/2003:10:41:03] WARNING (25931): CORE3283: stderr:      at com.tsp.gdgpo.ejbm.jcsms.sessionbeans.SpecialManagerEJBBean_EJBObjectImpl.listSpecialist(SpecialManagerEJBBean_EJBObjectImpl.java:702)
[12/Aug/2003:10:41:03] WARNING (25931): CORE3283: stderr:      at com.tsp.gdgpo.ejbm.jcsms.sessionbeans._SpecialManagerEJBBean_EJBObjectImpl_Tie._invoke(Unknown Source)thanks for any help
Niu

Ther is a related Bug i n Oracle: Bug No. 4420032
PROBLEM STATEMENT: ------------------
The Oracle client file ojdbc_14.jar is not handling exceptions correctly. The connection pool slowly runs out of connections and hits the oracle db limit of max_sessions. Increasing the db max_sessions does not help as the number of sessions continue to increase.
The vendor developers of ct's application have identified a code problem with the Oracle client file ojdbc_14.jar. Their description follows.
The following is a technical description of the Oracle JDBC client library issue. The jar file in question is: ojdbc_14.jar. This issue is also present in the 9.2.05 and 9.2.06 versions of the client code.
The socket.close() call in TcpNTAdapter.disconnect() does not properly handle network exceptions. Where the exception should be handled within the code segment calling socket.close(), the class instead throws an exception without ensuring the socket is closed. The socket is not subsequently closed by clients of the class. This ultimately results in a connection leak. Overtime, the maximum number of Oracle database sessions is reached. The only work around for this issue in production, is to restart the effected processes.
The code segment:
public void disconnect()
throws IOException {
socket.close();
socket = null; }
should be along the lines of:
public void disconnect()
throws IOException {
try{ socket.close(); }
catch(IOException ioe){ throw ioe; }
finally{ socket = null; } }
The original code segment will not execute the statement "socket = null" when . an exception occurs. Given the fact that the exception is not subsequently processed properly, the object is never dereferenced, and the socket remains open for the life of the process. Adding this statement in the finally block . ensures the object will ultimately be destroyed by the garbage collector. . ct tested this change in their lab and found that the recommended modification successfully resolved the issue.
This problem has occurred with the previous ct's application releases, but the vendor has only recently been able to isolate the root cause. The JDBC connection pool slowly runs out of connections and hits the oracle db limit of max_sessions.
Increasing the db max_sessions does not help as the number of sessions continue to increase. This problem has been occuring in Production over the past few releases of the application, but usually the connections leak slowly. This problem can be duplicated under heavy load in just a few minutes . in the Loadtest environment.

Deadlocks and very high wait times

We are seeing a very high number of deadlocks in the system. The deadlocks trace all show a 'enq: TX - row lock contention' with wait times of around 2929700+ seconds ex:
last wait for 'enq: TX - row lock contention' blocking sess=0x70000006d85e1b8 seq=55793 wait_time=2929704 seconds since wait started=4
name|mode=54580006, usn<<16 | slot=1d0010, sequence=705f
Dumping Session Wait History
for 'enq: TX - row lock contention' count=1 wait_time=2929704
name|mode=54580006, usn<<16 | slot=1d0010, sequence=705f
for 'latch: enqueue hash chains' count=1 wait_time=1649
address=70000006dbb4a20, number=13, tries=0
for 'enq: TX - row lock contention' count=1 wait_time=2929708
name|mode=54580006, usn<<16 | slot=1d0010, sequence=705f
for 'SQL*Net message from client' count=1 wait_time=101740
driver id=54435000, #bytes=1, =0
for 'SQL*Net message to client' count=1 wait_time=1
driver id=54435000, #bytes=1, =0
for 'direct path write temp' count=1 wait_time=921
file number=fb, first dba=6521b, block cnt=2
for 'SQL*Net more data from client' count=1 wait_time=3
driver id=54435000, #bytes=10, =0
for 'SQL*Net more data from client' count=1 wait_time=5
driver id=54435000, #bytes=1e, =0
for 'SQL*Net more data from client' count=1 wait_time=10
driver id=54435000, #bytes=2c, =0
for 'SQL*Net more data from client' count=1 wait_time=5
driver id=54435000, #bytes=3a, =0
Any ideas on how to resolve this ?
Thanks
Surya

Sorry for the typo, that Ora-0060 error we are seeing. Here is the deadlock graph:
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bit Production
With the Partitioning, Oracle Label Security, OLAP, Data Mining Scoring Engine
and Real Application Testing options
ORACLE_HOME = /orasw/product/10.2.0.4.0
System name: AIX
Node name: spda5001
Release: 3
Version: 5
Machine: 00074D5AD400
Instance name: IAMS01P1
Redo thread mounted by this instance: 1
Oracle process number: 21
Unix process pid: 2306444, image: oracle@spda5001
*** 2011-12-24 05:05:39.885
*** SERVICE NAME:(IAMS01P) 2011-12-24 05:05:39.884
*** SESSION ID:(443.2130) 2011-12-24 05:05:39.884
DEADLOCK DETECTED ( ORA-00060 )
[Transaction Deadlock]
The following deadlock is not an ORACLE error. It is a
deadlock due to user error in the design of an application
or from issuing incorrect ad-hoc SQL. The following
information may aid in determining the deadlock:
Deadlock graph:
---------Blocker(s)-------- ---------Waiter(s)---------
Resource Name process session holds waits process session holds waits
TX-00080020-000c3957 21 443 X 58 391 X
TX-001d0010-0000705f 58 391 X 21 443 X
session 443: DID 0001-0015-0000002E session 391: DID 0001-003A-00000081
session 391: DID 0001-003A-00000081 session 443: DID 0001-0015-0000002E
Rows waited on:
Session 391: obj - rowid = 0001098B - AAATtpAAGAAADROAAD
(dictionary objn - 67979, file - 6, block - 13390, slot - 3)
Session 443: obj - rowid = 00010B25 - AAARRwAAGAAAAdgAAN
(dictionary objn - 68389, file - 6, block - 1888, slot - 13)
Information on the OTHER waiting sessions:
Session 391:
pid=58 serial=16572 audsid=52790041 user: 93/IAMS_USR
O/S info: user: , term: , ospid: 1234, machine: mac3023
program:
Current SQL Statement:
update spt_identity set created=:1, modified=:2, owner=:3, assigned_scope=:4, assigned_scope_path=:5, extended1=:6, extended2=:7, extended3=:8, extended4=:9, extended5=:10, extended6=:11, extended7=:12, extended8=:13, extended9=:14, extended10=:15, extended11=:16, extended12=:17, extended13=:18, extended14=:19, extended15=:20, extended16=:21, extended17=:22, extended18=:23, extended19=:24, extended20=:25, name=:26, description=:27, protected=:28, iiqlock=:29, attributes=:30, manager=:31, display_name=:32, firstname=:33, lastname=:34, email=:35, manager_status=:36, inactive=:37, last_login=:38, last_refresh=:39, password=:40, password_expiration=:41, password_history=:42, bundle_summary=:43, assigned_role_summary=:44, correlated=:45, auth_question_lock_start=:46, failed_auth_question_attempts=:47, controls_assigned_scope=:48, certifications=:49, activity_config=:50, preferences=:51, history=:52, scorecard=:53, uipreferences=:54, attribute_meta_data=:55, workgroup=:56 where id=:57
End of information on OTHER waiting sessions.
Current SQL statement for this session:
update spt_workflow_case set created=:1, modified=:2, owner=:3, assigned_scope=:4, assigned_scope_path=:5, stack=:6, attributes=:7, launcher=:8, host=:9, launched=:10, completed=:11, progress=:12, percent_complete=:13, type=:14, messages=:15, name=:16, description=:17, complete=:18, target_class=:19, target_id=:20, target_name=:21, workflow=:22 where id=:23

Parameter for jdbc waiting time

I'm using wls5.1+sp10 on Solaris 8
I've configured 25 jdb connections in jdbc connection pool, but my
application will generate jdbc connection request more than that. All the
database calling are using CMP. I checked the document that we can configure
the waiting time for t3 driver. But I'm using Oracle OCI driver. Is there
any parameter I can tune to let the CMP to wait longer time to get the jdbc
connection? I found the default the value is 3 seconds which is too small
for me.
Thanks!

hi check the below link on JDBC adapter
http://help.sap.com/saphelp_nw70/helpdata/EN/96/791c42375d5033e10000000a155106/frameset.htm
https:/.../weblogs/sdn_weblogs_topics/pub/wlg/4183
recent enhancements to JDBC adapter
https:/.../weblogs/sdn_weblogs_topics/pub/wlg/1278
https:/.../weblogs/sdn_weblogs_topics/pub/wlg/4020
note:reward points if solution found helpfull.....
regards
chandrakanth.k

Inconsistent IO Wait Time

I'm trying to comprehend why oracle seems to more efficiently table scan a table when it has more rows than when it has less.
I have run a bunch of queries against the database, and I have tracked their wait events stats.
And it seems that this ratio:
ReacorsPerWait = #records/ wait_time,
where db_file_scattered_read is the most significant wait event by a lot
This Ratio simply Increases on and on, although the rate of increase grows eventually slower.
Namely, this ratio is practically the same when the relatio changes from 25 Million tuples to 125 Million tuples. But
before reaching that ratio threshold, the ratio increases quite significantly from test to test.
(From 0.2 Million to 1 million, to 5 million and to 25 Million...
It increases way too fast. I get changes in rate of more than 40%)
I just cannot make any sense of this performance change, If the number of records is increasing by 5 the IO time should also be increasing by 5.
What I have tried to do to fix this at some constant rate was: set the db_multiblock_read_count at some constant value. I set it up to like 10 MB. (10* 1024 KB / 8 KB)
But the results are the same, with or without a fixed multiblock read count, Oracle IOs faster when the relation is bigger. What is the cause of this? Any Ideas.
Another interesting thing is that the Cache Hit Ratio is reducing as the IO speed is increasing.
But the number of physical reads increase proportionately (times 5). I thought that this migh be explained because Oracle might Use larger Multi Block Reads when the relation was larger - or something like that.
But now I know that that cannot be the reason.
(By the way: this change in rate could be explained - partially - in the tests from 0.2Million to 1 million due to other wait time like reading control file, which is significant for small examples. But from 1 Million oward, approximately 99% of the wait time is doing the db file scattered read)
Edited by: sono99 on Nov 4, 2009 4:22 AM
Edited by: sono99 on Nov 4, 2009 4:30 AM
Edited by: sono99 on Nov 4, 2009 4:32 AM

sono99 wrote:
HI, thank you for trying to help.
"It's likely that measurements also vary with row size and not just row count ... not to mention half a dozen other features.
There are a couple of obvious possibilities:"I think that are not likely to be reason of the improvement in IO performance. Sure, I am not saying that standard deviation of row size is 0, but I'd say whichever the STD for the row size is, it will be pretty small.
To begin with, the table is populated with data generated by a home coocked program.
The table has like 6 collumns of integer type, none of them has null values.
If you ask a generic question you get generic answers.
Your original posting was about "the database", not about "a specific table created on a single disc for test purposes".
Have you tried cloning the table several times and seeing if the results are consistent across all clones ? There are several possible causes of variation in your case, for example has part of your table has ended up on a less fragmented part of the disc, or on the outer edge of the disc, so that the multiblock reads are more effective, or the disk-level track caching is more effective.
All sorts of strange side effects can appear when you create single user tests on small machines, and you have to be careful to consider the effects of multi-user activity on "realistic" system when constructing tests. It can be quite difficult to identify the points where a test is not properly representative of the mechanism you are trying to investigate.
Regards
Jonathan Lewis
http://jonathanlewis.wordpress.com
http://www.jlcomp.demon.co.uk
To post code, statspack/AWR report, execution plans or trace files, start and end the section with the tag {noformat}{noformat} (lowercase, curly brackets, no spaces) so that the text appears in fixed format.
"Science is more than a body of knowledge; it is a way of thinking"
Carl Sagan

Database Wait time calculation.

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