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From: Paolo Bonzini <pbonzini@redhat.com>
To: Asias He <asias.hejun@gmail.com>
Cc: Sasha Levin <levinsasha928@gmail.com>,
	Pekka Enberg <penberg@kernel.org>, Ingo Molnar <mingo@elte.hu>,
	Cyrill Gorcunov <gorcunov@gmail.com>,
	kvm@vger.kernel.org
Subject: Re: [PATCH] kvm tools: Process virito blk requests in separate thread
Date: Thu, 07 Jun 2012 10:47:37 +0200	[thread overview]
Message-ID: <4FD06AA9.1030606@redhat.com> (raw)
In-Reply-To: <CAFO3S42PsDSkh9Xa3qZMKL=A4XcfJ6N2oyqjbYf2Ku3P5_066g@mail.gmail.com>

Il 07/06/2012 03:38, Asias He ha scritto:
>> > I never looked at the kvmtool code, but I think Asias has a point.  If
>> > the guest submits I/O to lots of devices, they would contend on the
>> > single thread.  There was a similar proof of concept patch for QEMU that
>> > provided substantial benefit.
>> >
>> > However, it sounds a bit wasteful to have the dedicated thread run with
>> > a second eventfd.  Would it be hard to just use the virtio-blk ioeventfd
>> > directly?
> Without this patch, we are already using the virtio-blk ioeventfd
> which is being monitored in the shared ioeventfd__thread() thead.

Yes, I understood that. :)  I'm wondering why it is still necessary to
monitor that eventfd in the shared thread.  Perhaps you could optionally
skip the epoll registration/deregistration in ioeventfd__{add,del}_event.

Paolo

  reply	other threads:[~2012-06-07  8:47 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-06-04 15:40 [PATCH] kvm tools: Process virito blk requests in separate thread Asias He
2012-06-04 15:48 ` Cyrill Gorcunov
2012-06-05  0:47   ` Asias He
2012-06-05  6:10     ` Cyrill Gorcunov
2012-06-04 16:07 ` Sasha Levin
2012-06-05  1:03   ` Asias He
2012-06-05  8:14     ` Pekka Enberg
2012-06-06 12:35   ` Paolo Bonzini
2012-06-07  1:38     ` Asias He
2012-06-07  8:47       ` Paolo Bonzini [this message]
2012-06-08  3:30         ` Asias He
2012-06-05  8:15 ` Pekka Enberg
  -- strict thread matches above, loose matches on Subject: below --
2011-11-29 14:28 Asias He
2011-11-29 14:36 ` Sasha Levin
2011-11-30  7:21   ` Asias He
2011-12-01  8:48     ` Pekka Enberg
2011-12-01  8:58       ` Sasha Levin
2011-12-01 10:45         ` Pekka Enberg

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