Re: redo log sync time

Andreas Goldammer wrote:
>
> A few weeks ago I found a high average redo log sync time (40 ms)
> for my AIX database. I looked at the documentation and
> everything I found was tuning the I/O subsystem (SSA) or
> reduce the number of commits (impossible, we are using SAP R/3).
>
> Two weeks ago I moved the database to new hardware
> (new fast box, new fast adapters, new fast disks) and
> removed the AIX mirror from the online redo log filesystems
> to avoid the MWC impact (now I use ORACLE to mirror the log)
>
> The average redo log sync time remains steady, whereas
> other file access counters have decreased
>
> Any other ideas beside I/O and commits ?
>
> Thanks in advance
> Andreas
> mailto: agoldammer_at_viega.de

As well as Brian's info - you may get some benefit by lowering your log buffer size to get LGWR to wake up "earlier" in the transaction cycle.

HTH

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Connor McDonald
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"Some days you're the pigeon, some days you're the statue"