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Message-ID: <cd332ec7-2e29-419a-87a4-e32852ad96e7@acm.org>
Date: Tue, 20 Feb 2024 09:12:20 -0800
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Subject: Re: [PATCHv2 2/2] block: adjust CFS request expire time
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To: "zhaoyang.huang" <zhaoyang.huang@unisoc.com>,
 Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@redhat.com>,
 Juri Lelli <juri.lelli@redhat.com>,
 Vincent Guittot <vincent.guittot@linaro.org>, Jens Axboe <axboe@kernel.dk>,
 linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
 Zhaoyang Huang <huangzhaoyang@gmail.com>, steve.kang@unisoc.com
References: <20240220114536.513494-1-zhaoyang.huang@unisoc.com>
From: Bart Van Assche <bvanassche@acm.org>
In-Reply-To: <20240220114536.513494-1-zhaoyang.huang@unisoc.com>
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Where is patch 1/2 of this series? I don't see it in my mailbox.

On 2/20/24 03:45, zhaoyang.huang wrote:
> From: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
> 
> According to current policy, CFS's may suffer involuntary IO-latency by

Did you perhaps mean "cause" instead of "suffer"?

> being preempted by RT/DL tasks or IRQ.

For which workloads? Sequential I/O or random I/O? If it is for random I/O,
please take a look at patch "scsi: ufs: core: Add CPU latency QoS support
for UFS driver"
(https://lore.kernel.org/all/20231219123706.6463-1-quic_mnaresh@quicinc.com/)
and let us know whether or not the Power Management Quality of Service (PM QoS)
framework is perhaps a better solution.

Thanks,

Bart.