From: Paolo Valente <paolo.valente@linaro.org>
To: "Srivatsa S. Bhat" <srivatsa@csail.mit.edu>
Cc: linux-fsdevel@vger.kernel.org,
linux-block <linux-block@vger.kernel.org>,
linux-ext4@vger.kernel.org, cgroups@vger.kernel.org,
kernel list <linux-kernel@vger.kernel.org>,
Jens Axboe <axboe@kernel.dk>, Jan Kara <jack@suse.cz>,
Jeff Moyer <jmoyer@redhat.com>, Theodore Ts'o <tytso@mit.edu>,
amakhalov@vmware.com, anishs@vmware.com, srivatsab@vmware.com,
Ulf Hansson <ulf.hansson@linaro.org>,
Linus Walleij <linus.walleij@linaro.org>
Subject: Re: CFQ idling kills I/O performance on ext4 with blkio cgroup controller
Date: Thu, 13 Jun 2019 07:46:12 +0200 [thread overview]
Message-ID: <43486E4F-2237-4E40-BDFE-07CFCCFFFA25@linaro.org> (raw)
In-Reply-To: <7c5e9d11-4a3d-7df4-c1e6-7c95919522ab@csail.mit.edu>
[-- Attachment #1: Type: text/plain, Size: 2348 bytes --]
> Il giorno 12 giu 2019, alle ore 00:34, Srivatsa S. Bhat <srivatsa@csail.mit.edu> ha scritto:
>
> On 6/2/19 12:04 AM, Srivatsa S. Bhat wrote:
>> On 5/30/19 3:45 AM, Paolo Valente wrote:
>>>
> [...]
>>> At any rate, since you pointed out that you are interested in
>>> out-of-the-box performance, let me complete the context: in case
>>> low_latency is left set, one gets, in return for this 12% loss,
>>> a) at least 1000% higher responsiveness, e.g., 1000% lower start-up
>>> times of applications under load [1];
>>> b) 500-1000% higher throughput in multi-client server workloads, as I
>>> already pointed out [2].
>>>
>>
>> I'm very happy that you could solve the problem without having to
>> compromise on any of the performance characteristics/features of BFQ!
>>
>>
>>> I'm going to prepare complete patches. In addition, if ok for you,
>>> I'll report these results on the bug you created. Then I guess we can
>>> close it.
>>>
>>
>> Sounds great!
>>
>
> Hi Paolo,
>
Hi
> Hope you are doing great!
>
Sort of, thanks :)
> I was wondering if you got a chance to post these patches to LKML for
> review and inclusion... (No hurry, of course!)
>
I'm having troubles testing these new patches on 5.2-rc4. As it
happened with the first release candidates for 5.1, the CPU of my test
machine (Intel Core i7-2760QM@2.40GHz) is so slowed down that results
are heavily distorted with every I/O scheduler.
Unfortunately, I'm not competent enough to spot the cause of this
regression in a feasible amount of time. I hope it'll go away with
next release candidates, or I'll test on 5.1.
> Also, since your fixes address the performance issues in BFQ, do you
> have any thoughts on whether they can be adapted to CFQ as well, to
> benefit the older stable kernels that still support CFQ?
>
I have implanted my fixes on the existing throughput-boosting
infrastructure of BFQ. CFQ doesn't have such an infrastructure.
If you need I/O control with older kernels, you may want to check my
version of BFQ for legacy block, named bfq-sq and available in this
repo:
https://github.com/Algodev-github/bfq-mq/
I'm willing to provide you with any information or help if needed.
Thanks,
Paolo
> Thank you!
>
> Regards,
> Srivatsa
> VMware Photon OS
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next prev parent reply other threads:[~2019-06-13 16:46 UTC|newest]
Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-17 22:16 CFQ idling kills I/O performance on ext4 with blkio cgroup controller Srivatsa S. Bhat
2019-05-18 18:39 ` Paolo Valente
2019-05-18 19:28 ` Theodore Ts'o
2019-05-20 9:15 ` Jan Kara
2019-05-20 10:45 ` Paolo Valente
2019-05-21 16:48 ` Theodore Ts'o
2019-05-21 18:19 ` Josef Bacik
2019-05-21 19:10 ` Theodore Ts'o
2019-05-20 10:38 ` Paolo Valente
2019-05-21 7:38 ` Andrea Righi
2019-05-18 20:50 ` Srivatsa S. Bhat
2019-05-20 10:19 ` Paolo Valente
2019-05-20 22:45 ` Srivatsa S. Bhat
2019-05-21 6:23 ` Paolo Valente
2019-05-21 7:19 ` Srivatsa S. Bhat
2019-05-21 9:10 ` Jan Kara
2019-05-21 16:31 ` Theodore Ts'o
2019-05-21 11:25 ` Paolo Valente
2019-05-21 13:20 ` Paolo Valente
2019-05-21 16:21 ` Paolo Valente
2019-05-21 17:38 ` Paolo Valente
2019-05-21 22:51 ` Srivatsa S. Bhat
2019-05-22 8:05 ` Paolo Valente
2019-05-22 9:02 ` Srivatsa S. Bhat
2019-05-22 9:12 ` Paolo Valente
2019-05-22 10:02 ` Srivatsa S. Bhat
2019-05-22 9:09 ` Paolo Valente
2019-05-22 10:01 ` Srivatsa S. Bhat
2019-05-22 10:54 ` Paolo Valente
2019-05-23 2:30 ` Srivatsa S. Bhat
2019-05-23 9:19 ` Paolo Valente
2019-05-23 17:22 ` Paolo Valente
2019-05-23 23:43 ` Srivatsa S. Bhat
2019-05-24 6:51 ` Paolo Valente
2019-05-24 7:56 ` Paolo Valente
2019-05-29 1:09 ` Srivatsa S. Bhat
2019-05-29 7:41 ` Paolo Valente
2019-05-30 8:29 ` Srivatsa S. Bhat
2019-05-30 10:45 ` Paolo Valente
2019-06-02 7:04 ` Srivatsa S. Bhat
2019-06-11 22:34 ` Srivatsa S. Bhat
2019-06-12 13:04 ` Jan Kara
2019-06-12 19:36 ` Srivatsa S. Bhat
2019-06-13 6:02 ` Greg Kroah-Hartman
2019-06-13 19:03 ` Srivatsa S. Bhat
2019-06-13 8:20 ` Jan Kara
2019-06-13 19:05 ` Srivatsa S. Bhat
2019-06-13 8:37 ` Jens Axboe
2019-06-13 5:46 ` Paolo Valente [this message]
2019-06-13 19:13 ` Srivatsa S. Bhat
2019-05-23 23:32 ` Srivatsa S. Bhat
2019-05-30 8:38 ` Srivatsa S. Bhat
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