qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Kevin Wolf <kwolf@redhat.com>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: tom.leiming@gmail.com, Ming Lei <ming.lei@canonical.com>,
	Fam Zheng <famz@redhat.com>, qemu-devel <qemu-devel@nongnu.org>,
	Stefan Hajnoczi <stefanha@redhat.com>
Subject: Re: [Qemu-devel] [PATCH v1 00/17] dataplane: optimization and multi virtqueue support
Date: Mon, 18 Aug 2014 10:58:57 +0200	[thread overview]
Message-ID: <20140818085857.GA4111@noname.redhat.com> (raw)
In-Reply-To: <53F03DCE.3090909@redhat.com>

Am 17.08.2014 um 07:29 hat Paolo Bonzini geschrieben:
> Il 15/08/2014 22:15, Paolo Bonzini ha scritto:
> >> >                 | Random throughput | Sequential throughput
> >> > ----------------+-------------------+-----------------------
> >> > master          | 442 MB/s          | 730 MB/s
> >> > base            | 453 MB/s          | 757 MB/s
> >> > bypass (Ming)   | 461 MB/s          | 734 MB/s
> >> > coroutine       | 468 MB/s          | 716 MB/s
> >> > bypass (Paolo)  | 476 MB/s          | 682 MB/s
> > This is pretty large, but it really smells like either a setup problem
> > or a kernel bug...
> 
> Thinking more about the I/O scheduler, it could simply be that faster
> I/O = less coalescing = more bios actually reaching the driver = less speed.
> 
> It should be possible to find if this is true using blktrace.
> 
> (The reason why sequential I/O is faster is coalescing in the I/O
> scheduler).

Yes, sorry, should have posted an update on Friday. This was cfq in the
guest (apparently, the host doesn't use any scheduler with loop devices,
which makes some sense), with noop (or deadline) the numbers look much
better: Sequential throughput is on a slightly higher level and
increases with the optimisations, and random is much closer to it.

Kevin

  reply	other threads:[~2014-08-18  8:59 UTC|newest]

Thread overview: 81+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-08-05  3:33 [Qemu-devel] [PATCH v1 00/17] dataplane: optimization and multi virtqueue support Ming Lei
2014-08-05  3:33 ` [Qemu-devel] [PATCH v1 01/17] qemu/obj_pool.h: introduce object allocation pool Ming Lei
2014-08-05 11:55   ` Eric Blake
2014-08-05 12:05     ` Michael S. Tsirkin
2014-08-05 12:21       ` Eric Blake
2014-08-05 12:51         ` Michael S. Tsirkin
2014-08-06  2:35     ` Ming Lei
2014-08-05  3:33 ` [Qemu-devel] [PATCH v1 02/17] dataplane: use object pool to speed up allocation for virtio blk request Ming Lei
2014-08-05 12:30   ` Eric Blake
2014-08-06  2:45     ` Ming Lei
2014-08-05  3:33 ` [Qemu-devel] [PATCH v1 03/17] qemu coroutine: support bypass mode Ming Lei
2014-08-05  3:33 ` [Qemu-devel] [PATCH v1 04/17] block: prepare for supporting selective bypass coroutine Ming Lei
2014-08-05  3:33 ` [Qemu-devel] [PATCH v1 05/17] garbage collector: introduced for support of " Ming Lei
2014-08-05 12:43   ` Eric Blake
2014-08-05  3:33 ` [Qemu-devel] [PATCH v1 06/17] block: introduce bdrv_co_can_bypass_co Ming Lei
2014-08-05  3:33 ` [Qemu-devel] [PATCH v1 07/17] block: support to bypass qemu coroutinue Ming Lei
2014-08-05  3:33 ` [Qemu-devel] [PATCH v1 08/17] Revert "raw-posix: drop raw_get_aio_fd() since it is no longer used" Ming Lei
2014-08-05  3:33 ` [Qemu-devel] [PATCH v1 09/17] dataplane: enable selective bypassing coroutine Ming Lei
2014-08-05  3:33 ` [Qemu-devel] [PATCH v1 10/17] linux-aio: fix submit aio as a batch Ming Lei
2014-08-05  3:33 ` [Qemu-devel] [PATCH v1 11/17] linux-aio: handling -EAGAIN for !s->io_q.plugged case Ming Lei
2014-08-05  3:33 ` [Qemu-devel] [PATCH v1 12/17] linux-aio: increase max event to 256 Ming Lei
2014-08-05  3:33 ` [Qemu-devel] [PATCH v1 13/17] linux-aio: remove 'node' from 'struct qemu_laiocb' Ming Lei
2014-08-05  3:33 ` [Qemu-devel] [PATCH v1 14/17] hw/virtio/virtio-blk.h: introduce VIRTIO_BLK_F_MQ Ming Lei
2014-08-05  3:33 ` [Qemu-devel] [PATCH v1 15/17] virtio-blk: support multi queue for non-dataplane Ming Lei
2014-08-05  3:33 ` [Qemu-devel] [PATCH v1 16/17] virtio-blk: dataplane: support multi virtqueue Ming Lei
2014-08-05  3:33 ` [Qemu-devel] [PATCH v1 17/17] hw/virtio-pci: introduce num_queues property Ming Lei
2014-08-05  9:38 ` [Qemu-devel] [PATCH v1 00/17] dataplane: optimization and multi virtqueue support Stefan Hajnoczi
2014-08-05  9:50   ` Ming Lei
2014-08-05  9:56     ` Kevin Wolf
2014-08-05 10:50       ` Ming Lei
2014-08-05 13:59     ` Stefan Hajnoczi
2014-08-05  9:48 ` Kevin Wolf
2014-08-05 10:00   ` Ming Lei
2014-08-05 11:44     ` Paolo Bonzini
2014-08-05 13:48     ` Stefan Hajnoczi
2014-08-05 14:47       ` Kevin Wolf
2014-08-06  5:33         ` Ming Lei
2014-08-06  7:45           ` Paolo Bonzini
2014-08-06  8:38             ` Ming Lei
2014-08-06  8:50               ` Paolo Bonzini
2014-08-06 13:53                 ` Ming Lei
2014-08-06  8:48           ` Kevin Wolf
2014-08-06  9:37             ` Ming Lei
2014-08-06 10:09               ` Kevin Wolf
2014-08-06 11:28                 ` Ming Lei
2014-08-06 11:44                   ` Ming Lei
2014-08-06 15:40                   ` Kevin Wolf
2014-08-07 10:27                     ` Ming Lei
2014-08-07 10:52                       ` Ming Lei
2014-08-07 11:06                         ` Kevin Wolf
2014-08-07 13:03                           ` Ming Lei
2014-08-07 13:51                       ` Kevin Wolf
2014-08-08 10:32                         ` Ming Lei
2014-08-08 11:26                           ` Ming Lei
2014-08-10  3:46             ` Ming Lei
2014-08-11 14:03               ` Kevin Wolf
2014-08-12  7:53                 ` Ming Lei
2014-08-12 11:40                   ` Kevin Wolf
2014-08-12 12:14                     ` Ming Lei
2014-08-11 19:37               ` Paolo Bonzini
2014-08-12  8:12                 ` Ming Lei
2014-08-12 19:08                   ` Paolo Bonzini
2014-08-13  9:54                     ` Kevin Wolf
2014-08-13 13:16                       ` Paolo Bonzini
2014-08-13 13:49                         ` Ming Lei
2014-08-14  9:39                           ` Stefan Hajnoczi
2014-08-14 10:12                             ` Ming Lei
2014-08-15 20:16                             ` Paolo Bonzini
2014-08-13 10:19                     ` Ming Lei
2014-08-13 12:35                       ` Paolo Bonzini
2014-08-13  8:55                 ` Stefan Hajnoczi
2014-08-13 11:43                 ` Ming Lei
2014-08-13 12:35                   ` Paolo Bonzini
2014-08-13 13:07                     ` Ming Lei
2014-08-14 10:46                 ` Kevin Wolf
2014-08-15 10:39                   ` Ming Lei
2014-08-15 20:15                   ` Paolo Bonzini
2014-08-16  8:20                     ` Ming Lei
2014-08-17  5:29                     ` Paolo Bonzini
2014-08-18  8:58                       ` Kevin Wolf [this message]
2014-08-06  9:37           ` Stefan Hajnoczi

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=20140818085857.GA4111@noname.redhat.com \
    --to=kwolf@redhat.com \
    --cc=famz@redhat.com \
    --cc=ming.lei@canonical.com \
    --cc=pbonzini@redhat.com \
    --cc=qemu-devel@nongnu.org \
    --cc=stefanha@redhat.com \
    --cc=tom.leiming@gmail.com \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).