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Date: Tue, 11 May 2010 22:04:28 +0300
From: Avi Kivity <avi@redhat.com>
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Subject: Re: [Qemu-devel] Re: [PATCH 2/2] Add flush=off parameter to -drive
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To: Kevin Wolf <kwolf@redhat.com>
Cc: hch@lst.de, Alexander Graf <agraf@suse.de>, qemu-devel@nongnu.org

On 05/11/2010 11:36 AM, Kevin Wolf wrote:
> Am 10.05.2010 23:51, schrieb Alexander Graf:
>    
>> Usually the guest can tell the host to flush data to disk. In some cases we
>> don't want to flush though, but try to keep everything in cache.
>>
>> So let's add a new parameter to -drive that allows us to set the flushing
>> behavior to "on" or "off", defaulting to enabling the guest to flush.
>>
>> Signed-off-by: Alexander Graf<agraf@suse.de>
>>      
> What about another cache=... value instead of adding more options? I'm
> quite sure you'll only ever need this with writeback caching. So we
> could have cache=none|writethrough|writeback|wb-noflush or something
> like that.
>    

I implemented this once and promptly forgot about it, as cache=volatile.

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.