On 16.04.2008, at 01:24, PFC wrote:
>
>> The queries in question (select's) occasionally take up to 5 mins
>> even if they take ~2-3 sec under "normal" conditions, there are no
>> sequencial scans done in those queries. There are not many users
>> connected (around 3, maybe) to this database usually since it's
>> still in a testing phase. I tried to hunt down the problem by
>> playing around with resource usage cfg options but it didn't really
>> made a difference.
>
> Could that be caused by a CHECKPOINT ?


actually there are a few log (around 12 per day) entries concerning
checkpoints:

LOG: checkpoints are occurring too frequently (10 seconds apart)
HINT: Consider increasing the configuration parameter
"checkpoint_segments".

But wouldn't that only affect write performance? The main problems I'm
concerned about affect SELECT queries.

Regards,

Tom


PS: WAL settings are all set to defaults.

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