Re: Performance tuning question

> I just finished running some benchmarks on an underpowered server
> compared to the one I am running in production.
> My initial tests were run on an ampty database, pg_xlog on the same
> spindle.
> Stored procedure execution speed was ~15 ms.
>
> I then restored the production database so I would have ~3GB database.
> Execution time for the stored procedure went up to about 40 ms average
> (with a miuch higher variance), but with a processing speed of 18 stored
> procedure calls per second.
>
> I them moved pg_xlog to a separate spindle.
> Execution time went down to about 17 ms

Good!

> Beyond moving pg_xlog to a separate spindle, are there any other things
> you can think of which may improve the performance?

You could bundle more work into a single transaction.

I don't know what your call is doing, but 1 call that does 20 inserts in
a transaction is certainly more efficient than 2 calls doing two
transactions with 10 inserts each. If you can use bigger bundles of
work, do that.

Maybe reasoning in "MByte (or whatever) per second" rather than "time to
do a small piece of the work" helps. Otherwise you're into real time
stuff and RDBMS' and real time stuff don't mix well.

Bye :)
Chris.

--

Chris Mair
http://www.1006.org