linux-kernel - Re: [PATCH 9/9] block: loop: support to submit I/O via kernel aio based

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Date:	Mon, 28 Jul 2014 11:42:03 +0800
From:	Ming Lei <ming.lei@...onical.com>
To:	David Horner <ds2horner@...il.com>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 9/9] block: loop: support to submit I/O via kernel aio based

Hi David,

Thanks for your interest in the patch.

On Sun, Jul 27, 2014 at 10:20 PM, David Horner <ds2horner@...il.com> wrote:
> You mention > 100 % improvement.
>
> Can you help me to run some (micro) benchmarks that I could contribute to
> V1?

Sure, no problem, generally I just run tests over the loop block device
directly, since I want to expose performance improvement.  But I did
run test bench(mkfs, copy big file and compare, ...) over filesystem
mounted on the loop device too, and looks it is stable enough.

So your benchmarks are either on loop block or filesystem, both
are fine.

> If you can direct me to relevant threads and docs that would be greatly
> appreciated.

Follows my test which was observed with 100% improvement(
throughout is doubled, actually it is more than doubled):

- losetup -f /dev/nullb0   #so /dev/loop0 will be backed with /dev/nullb0
                                      #if it is the 1st loop device

- run below fio script[1] in single job to test direct randread on /dev/loop0

- it is just for single job improvement, with more than 1 jobs, the
throughout should be increased more with blk-mq conversion

I will send out V1 this week, and more test cases may be posted
too.

[1], fio test script
[global]
direct=1
size=32G
bsrange=4k-4k
timeout=20
numjobs=1
ioengine=libaio
iodepth=64
filename=/dev/loop0
group_reporting=1

[f]
rw=randread

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