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Home -> Community -> Mailing Lists -> Oracle-L -> Re: same sql, same execution plan, but the time to complete is very different when run in different time.
Wu,
Is there some other SQL or job running when you got your 'Bad
running'?Or the hardware, esp. disks were busy with backup?
On Nov 10, 2007 3:12 PM, qihua wu <staywithpin_at_gmail.com> wrote:
> Hi, we have a batch job(run throught SQLPLUS) which runs every day. For the
> same sql with the same execution plan, but the time spent on CPU is largely
> different. One is 781 seconds and another one is 2193 seconds. As buffer
> gets eat CPU, so I also compared the number of buffer gets and found the
> number of buffer gets are very close. SQL parsing also eats CPU, but the sql
> run millions of times inside a procedure, so it should be only parsed once,
> and one time of parse shouldn't use much CPU. What else can eat so much CPU?
>
>
>
>
> Elapsed Time (s)
>
> CPU Time (s)
>
> Executions
>
> Buffer Gets
>
> SQL Text
>
>
> Good running
>
> 829
>
> 781
>
> 1,587,382
>
> 96,640,879
>
> UPDATE PM_ELIGIBILITY_TEMP ELI...
>
>
> Bad running
>
> 2,978
>
> 2,193
>
> 1,587,382
>
> 96,642,211
>
> UPDATE PM_ELIGIBILITY_TEMP ELI...
>
> .
>
>
-- Yao Yongping Learning Oracle, UNIX/Linux... Love Reading, Classical Music, Philosophy, Economics etc. Blog: http://spaces.msn.com/yaoyp/ -- http://www.freelists.org/webpage/oracle-lReceived on Sat Nov 10 2007 - 09:44:58 CST
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