Re: New dirty tricks in Red Hat 5.x

From: Mladen Gogala <>
Date: Wed, 20 May 2009 21:26:43 +0000 (UTC)
Message-ID: <gv1sij$lg0$>

On Wed, 20 May 2009 09:35:40 -0700, joel garry wrote:

> Not sure I quite understand this own piece of disk thing, won't it be
> mooted by controller bottlenecks?

Of course, but that's not the point. The "ionice" command helps you prioritize I/O done by processes. The class 1 is "real time", the class 3 is "idle". Process in class 1 with the priority 0 has the highest I/O priority, any other process will have to wait for the LGWR to complete. If LGWR is the only process doing I/O on that particular disk, there will be no gain.

Received on Wed May 20 2009 - 16:26:43 CDT

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