Message-ID: <4D7496C5.6010900@fusionio.com>
Date: Mon, 7 Mar 2011 09:26:45 +0100
From: Jens Axboe <jaxboe@fusionio.com>
MIME-Version: 1.0
To: Shaohua Li <shaohua.li@intel.com>
CC: lkml <linux-kernel@vger.kernel.org>, Vivek Goyal <vgoyal@redhat.com>,
        Jeff Moyer <jmoyer@redhat.com>, Corrado Zoccolo <czoccolo@gmail.com>,
        Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Subject: Re: [PATCH]cfq-iosched: give busy sync queue no dispatch limit
References: <1299225689.2337.4.camel@sli10-conroe>
In-Reply-To: <1299225689.2337.4.camel@sli10-conroe>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 890
Lines: 21

On 2011-03-04 09:01, Shaohua Li wrote:
> If there are a sync and an async queue and the sync queue's think time is small,
> we can ignore the sync queue's dispatch quantum. Because the sync queue will
> always preempt the async queue, we don't need to care about async's latency.
> This can fix a performance regression of aiostress test, which is introduced by
> commit f8ae6e3eb825. The issue should exist even without the commit, but the
> commit amplifies the impact.
> 
> The initial post does the same optimization for RT queue too, but since I have
> no real workload for it, Vivek suggests to drop it.

Thanks, applied.

-- 
Jens Axboe

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/