Re: [PATCH v2 2/2] virtio-ring: Allocate indirect buffers from cache when possible

On 08/28/2012 03:20 PM, Michael S. Tsirkin wrote:

On Tue, Aug 28, 2012 at 03:04:03PM +0200, Sasha Levin wrote:

quoted

Currently if VIRTIO_RING_F_INDIRECT_DESC is enabled we will
use indirect descriptors and allocate them using a simple
kmalloc().

This patch adds a cache which will allow indirect buffers under
a configurable size to be allocated from that cache instead.

Signed-off-by: Sasha Levin <redacted>

I imagine this helps performance? Any numbers?

I ran benchmarks on the original RFC, I've re-tested it now and got similar
numbers to the original ones (virtio-net using vhost-net, thresh=16):

Before:
	Recv   Send    Send
	Socket Socket  Message  Elapsed
	Size   Size    Size     Time     Throughput
	bytes  bytes   bytes    secs.    10^6bits/sec

	 87380  16384  16384    10.00    4512.12

After:
	Recv   Send    Send
	Socket Socket  Message  Elapsed
	Size   Size    Size     Time     Throughput
	bytes  bytes   bytes    secs.    10^6bits/sec

	 87380  16384  16384    10.00    5399.18


Thanks,
Sasha