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  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 <>
To:	David Horner <>,
	Linux Kernel Mailing List <>
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 <> 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

[1], fio test script


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

Powered by blists - more mailing lists