From: Tom Lane <tgl@sss.pgh.pa.us>
To: Tobias Brox <tobias@nordicbet.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: "nice"/low priority Query
Date: Tue, 02 Aug 2005 12:19:30 -0400
Message-ID: <11484.1122999570@sss.pgh.pa.us> (raw)
In-Reply-To: <20050802160434.GD9278@tobias.lan>
References: <20050802160434.GD9278@tobias.lan>
Tobias Brox <tobias@nordicbet.com> writes:
> Is there any ways to give postgresql a hint that a
> particular SQL call should be run at lower priority? Since every db
> connection has a pid, I can manually run "renice" to scheduele it by the OS
> - but of course I can't do it manually all the time.
And it won't help you anyway, because renice only affects CPU priority
not I/O scheduling ... which, by your description, is the real problem.
I think the only thing that's likely to help much is trying to arrange
that the "simple" queries only need to touch pages that are already in
memory. Some playing around with shared_buffer sizing might help.
Also, if you're not on PG 8.0.*, an update might help.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, tobias@nordicbet.com
Subject: Re: "nice"/low priority Query
In-Reply-To: <11484.1122999570@sss.pgh.pa.us>
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