Re: session time model issue

From: Remigiusz Sokolowski <remigiusz.sokolowski_at_nordea.com>
Date: Wed, 9 Jan 2013 09:09:56 +0100
Message-ID: <50ED25D4.8060703_at_nordea.com>

On 09.01.2013 04:48, Jeremy Schneider wrote:
> On Tue, 8 Jan 2013 12:49:44 +0100
> Remigiusz Sokolowski <remigiusz.sokolowski_at_nordea.com> wrote:
>

>> I have just reviewed the session time model gathered for a single
>> query. My concern is that parse time elapsed is nearly 97% (and
>> actually the whole amount is attributed to hard parse) of the DB time
>> and sql execute elapsed time is 99% of the DB time.
>>
>> As this is for one session I assume there is no possibility the sum of
>> ingredients is more than DB time (of course by much), so it seems
>> reasonable to assume sql execute elapsed time is execute, fetch and
>> parse, which is against the docs.

>
>
> Hi Remigiusz,
>
> I don't think that execute time includes parsing or fetching. Could you
> give a little more detail about exactly what source data and
> calcuations you used to find the 97% and 99% on this one particular
> session?
>
> -Jeremy
>

I snap v$sess_time_model for the test session, then run a query and snap again. Then I just calculate the difference between snaps and percentage of every position to DB time as a base. The raw numbers are:
snap2:
DB time: 22784611
parse time elapsed: 21609770
sql execute elapsed time: 20780191
DB CPU: 11090000 snap1:
DB time: 5497118
parse time elapsed: 4847375
sql execute elapsed time: 3645675
DB CPU: 2060000 the rest is tens of thousands so negligible, so I do not provide. no parallel processing in use.

Regards
Remigiusz

-- 
Pole na kazi

----------------------------------------------------------------------
Remigiusz Sokolowski <remigiusz.sokolowski_at_nordea.com>
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Received on Wed Jan 09 2013 - 09:09:56 CET