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Date: Mon, 7 Nov 2011 16:49:48 +0800
Message-ID: <CAEH94LjMfbqYkoMaY6JMPDe_5xaFJ6b=dUwmL1Pxr9MQMK-hMw@mail.gmail.com>
From: Zhi Yong Wu <zwu.kernel@gmail.com>
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Subject: Re: [Qemu-devel] [v8 Patch 0/6]Qemu: Host pagecache setting from
 cmdline and monitor
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To: supriyak@linux.vnet.ibm.com
Cc: Kevin Wolf <kwolf@redhat.com>, Stefan Hajnoczi <stefanha@gmail.com>, qemu-devel@nongnu.org, Christoph Hellwig <hch@lst.de>

On Mon, Nov 7, 2011 at 4:38 PM, Supriya Kannery
<supriyak@linux.vnet.ibm.com> wrote:
> On 11/04/2011 07:59 AM, Zhi Yong Wu wrote:
>>
>> On Sun, Oct 30, 2011 at 6:33 PM, Supriya Kannery
>> <supriyak@linux.vnet.ibm.com> =A0wrote:
>>>
>>> Currently cache setting of a block device cannot be changed
>>> without restarting a running VM. Following patchset is for
>>> enabling dynamic change of cache setting for block devices
>>> through qemu monitor. Code changes are based on patches
>>> from Christoph Hellwig and Prerna Saxena.
>>>
>>> This patchset introduces
>>> a. monitor command 'block_set_hostcache' using which host
>>> =A0 pagecache setting for a block device can be changed
>>> =A0 dynamically.
>>
>> I got a bit confusion. Is it used to change host pagecache setting on
>> hyperviser or on guest?
>> This block device said by you is for guest, right?
>>
>
> =A0This command is used for changing pagecache setting of
> the image files in host which are acting as block devices
> for guest.
So what is the difference between it and cache option?

>
> -thanks, Supriya
>
>



--=20
Regards,

Zhi Yong Wu