Message-ID: <52670702.3030201@fuzzy.cz>
Date: Wed, 23 Oct 2013 01:15:14 +0200
From: Tomas Vondra <tv@fuzzy.cz>
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To: pgsql-performance@postgresql.org
Subject: Re: Hot Standby performance issue
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On 22.10.2013 23:50, sparikh wrote:
> Sorry, it was typo from my side. I meant strace only.

OK.

> 
> I will try to request both perf and strace to be installed. But I am
> not quite sure as the VMs are managed by third party. Will keep you
> posted...

What do you mean by VM? Is this a virtualized environment or bare hardware?

> 
> The main thing puzzling to me is Explain Plan with Analyze takes
> couple of secs to execute the operation but in reality it runs for
> more than 20 mins.

So, now I'm getting confused. Can you please provide timings for each
case. I.e. how long it takes to execute

1) plain query
2) explain query
3) explain analyze query

Execute each of those a couple of times, and let us know about
significant variations.

It should always be

       EXPLAIN ANALYZE >= query >= EXPLAIN

If you're reporting you see "EXPLAIN ANALYZE < query" then I find that
really strange.

Tomas


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