Re: A Question About Insertions -- Performance

Vivek Khera wrote:
> >>>>> "TL" == Tom Lane <tgl@sss.pgh.pa.us> writes:
>
> TL> My best guess is that the dropoffs occur because of background checkpoint
> TL> operations, but there's not enough info here to prove it.  Four inserts
> TL> per second seems horrendously slow in any case.
>
> I'll concur with this diagnosis.  I've been doing a bunch of
> performance testing with various parameter settings, and the
> checkpoint frequency is a big influence.  For me, by making the
> checkpoints occur as far apart as possible, the overall speed
> improvement was incredible.  Try bumping the number of
> checkpoint_segments in your postgresql.conf file.  For my tests I
> compared the default 3 with 50 segments.
>
> Check your logs to see if you are checkpointing too frequently.

That warning message is only in 7.4.

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