Re: rollback per transaction% - Statspack

"Thiru" <WantedToBeDBA_at_gmail.com> wrote in message news:1116584860.491531.141600_at_g44g2000cwa.googlegroups.com...
> Hi All,
> I want to know the root cause, which is making rollback per
> transaction% to 99.57.
>
> Also i noticed user rollbacks per transaction is 1. (i have attached
> the part of the statspack below)
> Does this mean that there is no transaction happened at all??
> Instance Activity Stats for DB: LMS Instance: ora9 Snaps: 931 -932
>
> Statistic Total per Second per Trans
> ------------------------- ------------------ --------------
> user calls 21,018,850 1,459.7 5.4
> user commits 16,699 1.2 0.0
> user rollbacks 3,860,461 268.1 1.0
>
> I don't see any failed transaction(I am doing web transaction using
> load testing tools which hits database). At the end of the test, i
> found that database is normal and its updated as expected.
> Is this situation really problem?? Does this situation signifies that
> the application is badly written by developer??
>
> Expecting Quick reply,
> Thiru.
>

I have found that some web application servers issue a rollback at the end of every single dialogue with the database - whether or not they have been updating or not. This is just a consequence of their attempts to handle connection pooling without running the risk of two different end-users managing to share a single (real) transaction.

Check the statistic

    rollback changed - undo records applied to see how much genuine rolling back is taking place.

-- 
Regards

Jonathan Lewis

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