From: Joshua D. Drake <jd@commandprompt.com>
To: Craig James <craig_james@emolecules.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Occasional giant spikes in CPU load
Date: Wed, 07 Apr 2010 14:40:10 -0700
Message-ID: <1270676410.19131.21.camel@jd-desktop.unknown.charter.com> (raw)
In-Reply-To: <4BBCFB12.1010306@emolecules.com>
References: <k2pda0294261004061437p9cd3810dqe9ce528b6ddb0873@mail.gmail.com>
<m2m603c8f071004071413w1f2d2497hbbe07d9c6491848f@mail.gmail.com>
<4BBCFB12.1010306@emolecules.com>
On Wed, 2010-04-07 at 14:37 -0700, Craig James wrote:
> Most of the time Postgres runs nicely, but two or three times a day we get a huge spike in the CPU load that lasts just a short time -- it jumps to 10-20 CPU loads. Today it hit 100 CPU loads. Sometimes days go by with no spike events. During these spikes, the system is completely unresponsive (you can't even login via ssh).
>
> I managed to capture one such event using top(1) with the "batch" option as a background process. See output below - it shows 19 active postgress processes, but I think it missed the bulk of the spike.
What does iostat 5 say during the jump?
Joshua D. Drake
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To: pgsql-performance@postgresql.org
Cc: jd@commandprompt.com, craig_james@emolecules.com
Subject: Re: Occasional giant spikes in CPU load
In-Reply-To: <1270676410.19131.21.camel@jd-desktop.unknown.charter.com>
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