I was recently
running a test with multiple client shell processes running psql commands
(inserts) when all the client processes appeared to hang simultaneously. I
assumed that I had an application deadlock somewhere, but after a few seconds -
less than a minute, but certainly noticeable - all the clients picked up again
and went on their way.
In the database log
at that time there was a "recycling transaction log" message which seems to
correspond to the time when the clients were paused, though I don't have it
concretely correlated.
I've seen these
messages in the log before, and am aware of the need to increase
checkpoint_segments, but I wasn't aware that recycling a transaction log could
be that damaging to performance. There may have been some local hiccup in this
case, but I'm wondering if recycling is known to be a big hit in general, and if
I should strive to tune so that it never happens (if that's
possible)?
Thanks.
-
DAP
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David
Parker Tazz Networks (401)
709-5130
