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Date: Wed, 26 Mar 2014 17:54:17 +0800
From: "Li, ZhenHua" <zhen-hual@hp.com>
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Subject: Re: [Qemu-devel] [PATCH 1/1] virtio-blk: Use a req pool instead of
 malloc/free
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To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: qemu-devel@nongnu.org

Stefan,

Thank you for your suggestions. I will try g_slice_* and give more 
performance testing results.

ZhenHua

On 03/26/2014 05:27 PM, Stefan Hajnoczi wrote:
> On Tue, Mar 25, 2014 at 04:44:48PM +0800, Li, Zhen-Hua wrote:
>> From: "Li, ZhenHua" <zhen-hual@hp.com>
>>
>> In virtio-blk module, when there is new request, new req structure
>> will be created by malloc.  Use a req pool instead of this, will increase
>> performance;
>>
>> Increacement: about 5% to 10%.
>>
>> Signed-off-by: Li, ZhenHua <zhen-hual@hp.com>
>> ---
>>   hw/block/virtio-blk.c |   87 ++++++++++++++++++++++++++++++++++++++++++-------
>>   1 file changed, 75 insertions(+), 12 deletions(-)
>
> Please try g_slice_new() instead of implementing a request pool
> manually:
> https://developer.gnome.org/glib/unstable/glib-Memory-Slices.html
>
> We already use g_slice_new() in other places in QEMU - for example in
> the virtio-blk dataplane code.
>
> Also please provide more details about the benchmark you are running.
> Which benchmark, what workload/settings, 5-10% increase of which number
> (IOPS, BW/CPU%, or something else), etc.
>
> Stefan
>