From: "Zhang Haoyu" <zhanghy@sangfor.com>
To: "Marcus White" <roastedseaweed.k@gmail.com>
Cc: kvm <kvm@vger.kernel.org>
Subject: Re: Some more basic questions..
Date: Tue, 3 Jun 2014 11:43:19 +0800 [thread overview]
Message-ID: <201406031143173652147@sangfor.com> (raw)
In-Reply-To: CALAJOd03U9mRkD0zA9-cfE7dP0v=1b9uE+k7-+KwaHDMW_CGow@mail.gmail.com
>A few additional questions:)
>
>1. If IO to a block device goes through QEMU and not vhost, are there
>data copies between kernel and user mode if I do IO to a block device
>or is it zero copy? Kind of related to Question (2) also.
>
I'm not sure, it perhaps depend on which IO mode you chose, qemu pthreads IO, or linux AIO?
Somebody else do a favour, please.
>2. A related question to (1), is the QEMU process separate from the VM
>process or do they all run on the same process as different threads? I
>did read about IO threads and it seemed like they are all part of the
>same process, wanted to confirm.
>
Yes, vcpu threads and qemu backend IO threads belong to the same process(qemu).
>Thank you:)
next prev parent reply other threads:[~2014-06-03 3:43 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-05-28 20:59 Some more basic questions Marcus White
2014-05-29 6:04 ` Venkateswara Rao Nandigam
2014-05-29 6:45 ` Zhang Haoyu
2014-05-30 4:06 ` Marcus White
2014-05-30 6:48 ` Zhang Haoyu
2014-06-02 21:19 ` Marcus White
2014-06-03 3:43 ` Zhang Haoyu [this message]
2014-06-03 4:53 ` Marcus White
2014-06-03 6:47 ` Zhang Haoyu
2014-06-03 6:54 ` Venkateswara Rao Nandigam
2014-06-03 11:00 ` Zhang Haoyu
2014-06-03 11:25 ` Venkateswara Rao Nandigam
2014-06-04 1:08 ` Marcus White
2014-06-05 4:42 ` Marcus White
2014-06-12 18:48 ` Marcus White
2014-06-03 12:51 ` Zhang Haoyu
-- strict thread matches above, loose matches on Subject: below --
2003-11-10 4:15 Alejandro Sanchez Acosta
2003-11-10 12:17 ` Alex Zarochentsev
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