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Date: Mon, 24 Sep 2012 19:32:46 +0800
From: ching <lsching17@gmail.com>
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Subject: [Qemu-devel] linux aio and cache mode
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To: qemu-devel@nongnu.org

Hi all,

My host is qemu-1.1.1 and x64 kernel 3.5.4. The guest is using aio="native"

I am trying to use unsafe cache mode to boost i/o performance.

After googling a while, there are some old web page telling that linux native aio do not use host cache. (http://stackoverflow.com/questions/5664105/buffered-asynchronous-file-i-o-on-linux)

is it still valid for recent kernel? do i need to change to aio="threads" to take advantage of unsafe cache mode?

Thanks in advance.

Regards,
ching