linux-kernel - Re: scsi-mq

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

Message-ID: <53A05068.4080702@acm.org>
Date:	Tue, 17 Jun 2014 16:27:52 +0200
From:	Bart Van Assche <bvanassche@....org>
To:	Christoph Hellwig <hch@....de>,
	James Bottomley <James.Bottomley@...senPartnership.com>
CC:	Jens Axboe <axboe@...nel.dk>,
	Bart Van Assche <bvanassche@...ionio.com>,
	Robert Elliot <Elliott@...com>, linux-scsi@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: scsi-mq

On 06/12/14 15:48, Christoph Hellwig wrote:
> Bart and Robert have helped with some very detailed measurements that they
> might be able to send in reply to this, although these usually involve
> significantly reworked low level drivers to avoid other bottle necks.

In case someone would like to see the results of the measurements I ran,
these results can be found here:
https://docs.google.com/file/d/0B1YQOreL3_FxUXFMSjhmNDBNNTg.

Two important conclusions from the data in that PDF document are as follows:
- A small but significant performance improvement for the traditional
  SCSI mid-layer (use_blk_mq=N).
- A very significant performance improvement for multithreaded
  workloads with use_blk_mq=Y. As an example, the number of I/O
  operations per second reported for the random write test increased
  with 170%. That means 2.7 times the performance
  of use_blk_mq=N.

I think this means the scsi-mq patches are ready for wider use.

Bart.
--
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/