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Date: Thu, 22 Mar 2012 13:55:28 +0100
Subject: Re: Write workload is causing severe slowdown in
 Production
From: "Tomas Vondra" <tv@fuzzy.cz>
To: gnanam@zoniac.com
Cc: "'Tomas Vondra'" <tv@fuzzy.cz>, "'Vitalii Tymchyshyn'" <tivv00@gmail.com>,
	pgsql-performance@postgresql.org
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On 22 B=C5=99ezen 2012, 13:10, Gnanakumar wrote:
>> So, what else is running on the system? Because if there's 35GB RAM an=
d
>> the shared buffers are 1.5GB, then there's about 33GB for page cache.
>> Something like 16GB would be a conservative setting.
>
> Yes, you guessed it right.  Both Web server and DB server are running i=
n
> the same machine.
>
>> I'm not saying this will fix the issues, but maybe it shows that
>> something
>> else is running on the box and maybe that's the culprit, not PostgreSQ=
L?
>
> Based on my observations and analysis, I'm sure that database write
> operation "is" causing the slowdown, but not because of other applicati=
ons
> running in the same server.

You haven't provided any clear evidence for such statement so far. Let's
wait for the vmstat/iostat logs etc.

Tomas