On Wed, Feb 02, 2011 at 07:42:51AM -0800, Shirley Ma wrote:

On Wed, 2011-02-02 at 12:49 +0200, Michael S. Tsirkin wrote:

quoted

On Tue, Feb 01, 2011 at 11:33:49PM -0800, Shirley Ma wrote:

quoted

On Tue, 2011-02-01 at 23:14 -0800, Shirley Ma wrote:

quoted

w/i guest change, I played around the parameters,for example: I

could

quoted

quoted

get 3.7Gb/s with 42% CPU BW increasing from 2.5Gb/s for 1K message
size,
w/i dropping packet, I was able to get up to 6.2Gb/s with similar

CPU

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usage. 

I meant w/o guest change, only vhost changes. Sorry about that.

Shirley

Ah, excellent. What were the parameters? 

I used half of the ring size 129 for packet counters,
but the
performance is still not as good as dropping packets on guest, 3.7 Gb/s
vs. 6.2Gb/s.

Shirley

How many packets and bytes per interrupt are sent?
Also, what about other values for the counters and other counters?

What does your patch do? Just drop packets instead of
stopping the interface?

To have an understanding when should we drop packets
in the guest, we need to know *why* does it help.
Otherwise, how do we know it will work for others?
Note that qdisc will drop packets when it overruns -
so what is different? Also, are we over-running some other queue
somewhere?

-- 
MST