Re: query slow only after reboot

From: "Kevin Grittner" <Kevin(dot)Grittner(at)wicourts(dot)gov>
To: "Wei Yan" <weiyan1(at)gmail(dot)com>,<pgsql-performance(at)postgresql(dot)org>
Subject: Re: query slow only after reboot
Date: 2009-02-10 15:00:54
Message-ID: 49914246.EE98.0025.0@wicourts.gov
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>>> Wei Yan <weiyan1(at)gmail(dot)com> wrote:
> Our queries are extremely slow only after db server reboot

> Any suggestion on how to tackle the problem?

Others have addressed how you can try to prime your cache after a
reboot, so I'll mention the 800 pound gorilla sitting in the corner.
I suggest you don't reboot as often, and when you have to do so,
schedule it off-hours, when there is time for the cache to get
populated with minimal pain.

We basically don't reboot our database servers except when we upgrade
the kernel. Even when we were running Windows as the OS on some
servers we were able to tune it so that reboots could be relatively
infrequent by aggressively disabling services and daemons down to the
bare minimum.

-Kevin

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