On Mar 14, 2006, at 1:31 PM, Casey Duncan wrote:
On Mar 13, 2006, at 5:25 PM, Casey Duncan wrote:
[..]
If I restart the postmaster, the query will complete in the expected
time.
Does the problem eventually start happening again? If so, after
how long? How did you determine that the restart is relevant? Do
you consistently see different (presumably better) performance after
a restart than if you don't restart?
I restarted postgres this morning and this time it didn't seem to
help. That query has been running for several hours now. I'm going to
let it go a while longer to see if it eventually completes, but I
suspect it won't. So perhaps the prior restart was just dumb luck.
I'll try some narrower queries as well.
Interestingly, I can only narrow the query by about an hour (i.e., a 23
hour span) before the plan changes to a simple index scan. That may
explain why this only started hanging recently since it probably only
started using the bitmap scan for a day interval recently.
Let me know if there is anything I should do or any info you need to
further pin this down.
In the mean time I will disable bitmap scans for this query.
Thanks.
-Casey
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