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Date: Thu, 24 Jan 2008 17:07:03 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Jens Axboe <jens.axboe@oracle.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Make idle iopriority class safe for non-root
Message-ID: <20080124160703.GE4857@elte.hu>
References: <20080123101142.GJ6258@kernel.dk>
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* Jens Axboe <jens.axboe@oracle.com> wrote:

> Hi,
> 
> Currently you must be root to set idle io prio class on a process. 
> This is due to the fact that the idle class is implemented as a true 
> idle class, meaning that it will not make progress if someone else is 
> requesting disk access. Unfortunately this means that it opens DOS 
> opportunities by locking down file system resources, hence it is root 
> only at the moment.
> 
> This patch relaxes the idle class a little, by removing the truly idle 
> part (which entals a grace period with associated timer). The 
> modifications make the idle class as close to zero impact as can be 
> done while still guarenteeing progress. This means we can relax the 
> root only criteria as well.

nice stuff!

	Ingo