From: Matias Bjorling <m@bjorling.me>
To: Andras Kovacs <neoteny@freemail.hu>, linux-scsi@vger.kernel.org
Subject: Re: blk-mq, scsi-mq, UFS
Date: Sat, 27 Sep 2014 19:42:42 +0200 [thread overview]
Message-ID: <5426F712.3010501@bjorling.me> (raw)
In-Reply-To: <loom.20140927T001325-865@post.gmane.org>
On 09/27/2014 12:14 AM, Andras Kovacs wrote:
> Hi all,
>
> could someone explain to me:
>
> - what is the difference between blk-mq and scsi-mq
blk-mq is the actual block layer, while scsi-mq enables the scsi
subsystem to use blk-mq. Any driver that wish to use blk-mq, has to
explicit hook into it.
> - why don't I observe large speedups when running the same tiotests on Linux
> v3.12 (which has no blk-mq) and Linux v3.14 (which does have blk-mq) on a
> Xilinx Zynq development board (the two Linux versions are configured by
> Xilinx Zynq and I know only how to add kernel command line parameters)?
Only the virtio driver (and the null blk driver) have been converted to
blk-mq in 3.14.
> - when Linux v3.17 becomes available (and Xilinx Zynq ports it for their
> development board) will I see large speedups reading/writing to the target
> SDD (which is driven through the UFS driver)?
Depends if you're CPU bound. If you are, then a speedup is expected. You
will at least see lower CPU usage.
scsi-mq has to be explicit enabled with the scsi_mod.use_blk_mq=Y in the
kernel boot options for 3.17 until it is marked stable.
>
> Any and all info would be greatly appreciated.
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
next prev parent reply other threads:[~2014-09-27 17:42 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-09-26 22:14 blk-mq, scsi-mq, UFS Andras Kovacs
2014-09-26 22:31 ` Andras Kovacs
2014-09-27 17:42 ` Matias Bjorling [this message]
2014-09-27 23:08 ` Andras Kovacs
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=5426F712.3010501@bjorling.me \
--to=m@bjorling.me \
--cc=linux-scsi@vger.kernel.org \
--cc=neoteny@freemail.hu \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.