From: Tomas Vondra <tv@fuzzy.cz>
To: pgsql-performance@postgresql.org
Subject: Re: Hot Standby performance issue
Date: Sat, 02 Nov 2013 20:40:23 +0100
Message-ID: <52755527.7000902@fuzzy.cz> (raw)
In-Reply-To: <1382991814055-5776156.post@n5.nabble.com>
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On 28.10.2013 21:23, sparikh wrote:
> Hi,
>
> Yes, you are right. The table is the biggest one . Please find below the
> information you requested. I agree the fact that autovacuum ran on this
> table would fix the performance issue on standby does not sound very
> convincing. But that is the only thing I could correlate when the query on
> standby started working again. Otherwise there is absolutely no changes at
> code level , database level or OS level.
> As of now query is still working fine on standby.
>
> I may be wrong, but could it be the case that standby disk was too much
> fragmented compare to primary and autovaccum on primary fixed that.
> (Assuming autovacuum on primary internally triggers the same on standby)
I find it very unlikely, but you didn't gave us necessary data (say, how
much free space was on the disks, etc.). The best way to pinpoint the
issue would be to run some profiler (which we have repeatedly asked you
to do), but now that the issue disappeared we can only guess.
Please monitor the system and if it happens again run perf or other
profiler so that we know where the time is spent.
Tomas
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To: pgsql-performance@postgresql.org
Cc: tv@fuzzy.cz
Subject: Re: Hot Standby performance issue
In-Reply-To: <52755527.7000902@fuzzy.cz>
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