RE: INSERT Performance in Benchmark ? ... Basic Qs
Date: Sat, 21 Jun 2008 02:02:59 +0800
Note that you could be hitting one of the multiple ASSM bugs related to indexes. Like this one for example:
Bug # 4664513 Slow Insert - Waiting For 'log File Sync' - High 'transaction
( Base bug# 4288876 )
You can easily diagnose it - if you see "transaction rollbacks" in V$SESSTAT increasing without corresponding "user rollbacks" for that session (you can use Snapper of taking snapshots). Another symptom is that you see "log file sync" waits during inserts even if you are not committing (as the session waits for log file sync when a transaction rollback happens as well).
-- Regards, Tanel Poder http://blog.tanelpoder.comReceived on Fri Jun 20 2008 - 13:02:59 CDT
> -----Original Message-----
> From: oracle-l-bounce_at_freelists.org
> [mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Tim Gorman
> Sent: Saturday, June 21, 2008 00:46
> To: VIVEK_SHARMA_at_infosys.com
> Cc: oracle-l_at_freelists.org; mwf_at_rsiz.com; rjamya;
> richa03_at_gmail.com; Tanel Poder; hrishys_at_yahoo.co.uk;
> finn.oracledba_at_gmail.com; anjo.kolk_at_oraperf.com
> Subject: RE: INSERT Performance in Benchmark ? ... Basic Qs
> One of the pitfalls to TKPROF is that none of the "sort"
> options (yet) include wait event timings, except perhaps
> "elapsed", but still not perfectly.
> Please be sure to specify "sort=prsela,exeela,fchela" on the
> TKPROF command-line for the best results.