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From: Stefan Hajnoczi <stefanha@gmail.com>
To: 解壁伟 <xiebiwei@ict.ac.cn>
Cc: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] About the Thread model in Qemu【 Is it one thread per vcpu?】
Date: Wed, 13 Mar 2013 09:45:40 +0100	[thread overview]
Message-ID: <20130313084540.GB14391@stefanha-thinkpad.muc.redhat.com> (raw)
In-Reply-To: <513EF6A0.4000601@ict.ac.cn>

On Tue, Mar 12, 2013 at 05:34:24PM +0800, 解壁伟 wrote:
> Hi there:
> 
> I've read this an article discribe the thread model in Qemu.
> http://blog.vmsplice.net/2011/03/qemu-internals-overall-architecture-and.html
> Is there really one thread per vcpu in qemu?
> 
> When I run the qemu using "-smp 16", I can see only two threads using
> "ps -xH".

"Note that TCG is not thread-safe so even under the iothread model it
multiplexes vcpus across a single QEMU thread. Only KVM can take
advantage of per-vcpu threads."

If you do not have -enable-kvm then you're probably using TCG.

Stefan

  parent reply	other threads:[~2013-03-13  8:46 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-03-12  9:34 [Qemu-devel] About the Thread model in Qemu【 Is it one thread per vcpu?】 解壁伟
2013-03-12 22:26 ` Laszlo Ersek
2013-03-13  8:59   ` 解壁伟
2013-03-13  8:45 ` Stefan Hajnoczi [this message]
2013-03-13  9:32   ` 解壁伟
2013-03-13  9:51     ` Peter Maydell
2013-03-13  9:56       ` Laurent Desnogues
2013-03-13 12:21         ` Paolo Bonzini
2013-04-15 14:43 ` [Qemu-devel] Round robin of multi-vcpu in qemu 解壁伟
2013-04-23  1:25   ` 陳韋任 (Wei-Ren Chen)

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