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Date: Thu, 20 May 2010 08:40:06 -0500
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: Re: [Qemu-devel] [PATCH] QEMU: change default disk cache behavior
References: <1274347924-9188-1-git-send-email-Jes.Sorensen@redhat.com>
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To: Jes Sorensen <Jes.Sorensen@redhat.com>
Cc: hch@infradead.org, aliguori@us.ibm.com, qemu-devel@nongnu.org, crobinso@redhat.com

On 05/20/2010 08:36 AM, Jes Sorensen wrote:
> On 05/20/10 14:30, Anthony Liguori wrote:
>    
>> On 05/20/2010 04:32 AM, Jes.Sorensen@redhat.com wrote:
>>      
>>> Therefore, here is a patch that does two things:
>>>    - default to "nocache"
>>>    - in case of failure with nocache, retry with "write-back"
>>>
>>>        
>> This sort of change requires performance data in a variety of
>> circumstances to justify.
>>
>> And I strongly suspect that such a blanket change would be wrong but
>> that a more targeted change like making cache=none default for physical
>> devices would satisfy mostly everyone.
>>      
> Is there any other thing than physical devices attached to the -drive
> parameter?
>    

Image files which are the overwhelming more common use-case.

Regards,

Anthony Liguori

> If so, I can take a look at making it more generic when I am back from
> holiday next week.
>
> Jes
>
>