From: Paolo Bonzini <pbonzini@redhat.com>
To: Avi Kivity <avi@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>,
Stefan Hajnoczi <stefanha@gmail.com>,
Anthony Liguori <aliguori@us.ibm.com>,
Ping Fan Liu <pingfank@linux.vnet.ibm.com>,
qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] Block I/O outside the QEMU global mutex was "Re: [RFC PATCH 00/17] Support for multiple "AIO contexts""
Date: Tue, 09 Oct 2012 12:36:42 +0200 [thread overview]
Message-ID: <5073FE3A.1090903@redhat.com> (raw)
In-Reply-To: <5073EDB3.3020804@redhat.com>
Il 09/10/2012 11:26, Avi Kivity ha scritto:
> On 10/09/2012 11:08 AM, Stefan Hajnoczi wrote:
>> Here are the steps that have been mentioned:
>>
>> 1. aio fastpath - for raw-posix and other aio block drivers, can we reduce I/O
>> request latency by skipping block layer coroutines?
>
> Is coroutine overhead noticable?
I'm thinking more about throughput than latency. If the iothread
becomes CPU-bound, then everything is noticeable.
>> I'm also curious about virtqueue_pop()/virtqueue_push() outside the QEMU mutex
>> although that might be blocked by the current work around MMIO/PIO dispatch
>> outside the global mutex.
>
> It is, yes.
It should only require unlocked memory map/unmap, not MMIO dispatch.
The MMIO/PIO bits are taken care of by ioeventfd.
Paolo
next prev parent reply other threads:[~2012-10-09 10:36 UTC|newest]
Thread overview: 72+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-09-25 12:55 [Qemu-devel] [RFC PATCH 00/17] Support for multiple "AIO contexts" Paolo Bonzini
2012-09-25 12:55 ` [Qemu-devel] [PATCH 01/17] build: do not rely on indirect inclusion of qemu-config.h Paolo Bonzini
2012-09-25 12:55 ` [Qemu-devel] [PATCH 02/17] event_notifier: enable it to use pipes Paolo Bonzini
2012-10-08 7:03 ` Stefan Hajnoczi
2012-09-25 12:55 ` [Qemu-devel] [PATCH 03/17] event_notifier: add Win32 implementation Paolo Bonzini
2012-09-25 12:55 ` [Qemu-devel] [PATCH 04/17] aio: change qemu_aio_set_fd_handler to return void Paolo Bonzini
2012-09-25 21:47 ` Anthony Liguori
2012-09-25 12:55 ` [Qemu-devel] [PATCH 05/17] aio: provide platform-independent API Paolo Bonzini
2012-09-25 21:48 ` Anthony Liguori
2012-09-25 12:55 ` [Qemu-devel] [PATCH 06/17] aio: introduce AioContext, move bottom halves there Paolo Bonzini
2012-09-25 21:51 ` Anthony Liguori
2012-09-26 6:30 ` Paolo Bonzini
2012-09-25 12:55 ` [Qemu-devel] [PATCH 07/17] aio: add I/O handlers to the AioContext interface Paolo Bonzini
2012-09-25 12:55 ` [Qemu-devel] [PATCH 08/17] aio: add non-blocking variant of aio_wait Paolo Bonzini
2012-09-25 21:56 ` Anthony Liguori
2012-09-25 12:55 ` [Qemu-devel] [PATCH 09/17] aio: prepare for introducing GSource-based dispatch Paolo Bonzini
2012-09-25 22:01 ` Anthony Liguori
2012-09-26 6:36 ` Paolo Bonzini
2012-09-26 6:48 ` Paolo Bonzini
2012-09-29 11:28 ` Blue Swirl
2012-10-01 6:40 ` Paolo Bonzini
2012-09-25 12:55 ` [Qemu-devel] [PATCH 10/17] aio: add Win32 implementation Paolo Bonzini
2012-09-25 12:55 ` [Qemu-devel] [PATCH 11/17] aio: make AioContexts GSources Paolo Bonzini
2012-09-25 22:06 ` Anthony Liguori
2012-09-26 6:40 ` Paolo Bonzini
2012-09-25 12:55 ` [Qemu-devel] [PATCH 12/17] aio: add aio_notify Paolo Bonzini
2012-09-25 22:07 ` Anthony Liguori
2012-09-25 12:55 ` [Qemu-devel] [PATCH 13/17] aio: call aio_notify after setting I/O handlers Paolo Bonzini
2012-09-25 22:07 ` Anthony Liguori
2012-09-25 12:56 ` [Qemu-devel] [PATCH 14/17] main-loop: use GSource to poll AIO file descriptors Paolo Bonzini
2012-09-25 22:09 ` Anthony Liguori
2012-09-26 6:38 ` Paolo Bonzini
2012-09-25 12:56 ` [Qemu-devel] [PATCH 15/17] main-loop: use aio_notify for qemu_notify_event Paolo Bonzini
2012-09-25 22:10 ` Anthony Liguori
2012-09-25 12:56 ` [Qemu-devel] [PATCH 16/17] aio: clean up now-unused functions Paolo Bonzini
2012-09-25 22:11 ` Anthony Liguori
2012-09-25 12:56 ` [Qemu-devel] [PATCH 17/17] linux-aio: use event notifiers Paolo Bonzini
2012-09-26 12:28 ` [Qemu-devel] [RFC PATCH 00/17] Support for multiple "AIO contexts" Kevin Wolf
2012-09-26 13:32 ` Paolo Bonzini
2012-09-26 14:31 ` Kevin Wolf
2012-09-26 15:48 ` Paolo Bonzini
2012-09-27 7:11 ` Kevin Wolf
2012-09-27 7:43 ` Paolo Bonzini
2012-10-08 11:39 ` Stefan Hajnoczi
2012-10-08 13:00 ` Paolo Bonzini
2012-10-09 9:08 ` [Qemu-devel] Block I/O outside the QEMU global mutex was "Re: [RFC PATCH 00/17] Support for multiple "AIO contexts"" Stefan Hajnoczi
2012-10-09 9:26 ` Avi Kivity
2012-10-09 10:36 ` Paolo Bonzini [this message]
2012-10-09 10:52 ` Avi Kivity
2012-10-09 11:08 ` Paolo Bonzini
2012-10-09 11:55 ` Avi Kivity
2012-10-09 12:01 ` Paolo Bonzini
2012-10-09 12:18 ` Jan Kiszka
2012-10-09 12:28 ` Avi Kivity
2012-10-09 12:22 ` Avi Kivity
2012-10-09 13:11 ` Paolo Bonzini
2012-10-09 13:21 ` Avi Kivity
2012-10-09 13:50 ` Paolo Bonzini
2012-10-09 14:24 ` Avi Kivity
2012-10-09 14:35 ` Paolo Bonzini
2012-10-09 14:41 ` Avi Kivity
2012-10-09 14:05 ` Stefan Hajnoczi
2012-10-09 15:02 ` Anthony Liguori
2012-10-09 15:06 ` Paolo Bonzini
2012-10-09 15:37 ` Anthony Liguori
2012-10-09 16:26 ` Paolo Bonzini
2012-10-09 18:26 ` Anthony Liguori
2012-10-10 7:11 ` Paolo Bonzini
2012-10-10 12:25 ` Anthony Liguori
2012-10-10 13:31 ` Paolo Bonzini
2012-10-10 14:44 ` Anthony Liguori
2012-10-11 12:28 ` Kevin Wolf
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=5073FE3A.1090903@redhat.com \
--to=pbonzini@redhat.com \
--cc=aliguori@us.ibm.com \
--cc=avi@redhat.com \
--cc=kwolf@redhat.com \
--cc=pingfank@linux.vnet.ibm.com \
--cc=qemu-devel@nongnu.org \
--cc=stefanha@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).