Re: [kvm-devel] [PATCH 0/2] Batch writes to MMIO

[Laurent V. <Lau...@bu...>]

Le mercredi 23 avril 2008 à 10:10 -0500, Anthony Liguori a écrit :
[...]
> The ne2k is pretty mmio heavy.  You should be able to observe a boost 
> with something like iperf (guest=>host) I would think if this is a real 
> savings.

I like your advices :-D

I use iperf with e1000 emulation and a slightly modified patch (to
detect MMIO write in a loop), server is on the host, client on the
guest, with default values.

RESULT WITHOUT BATCHING:

[  4]  0.0-10.0 sec    235 MBytes    197 Mbits/sec
[  5]  0.0-10.0 sec    194 MBytes    163 Mbits/sec
[  4]  0.0-10.0 sec    185 MBytes    155 Mbits/sec
[  5]  0.0-10.0 sec    227 MBytes    190 Mbits/sec
[  4]  0.0-10.0 sec    196 MBytes    164 Mbits/sec
[  5]  0.0-10.0 sec    194 MBytes    163 Mbits/sec
[  4]  0.0-10.0 sec    184 MBytes    154 Mbits/sec

RESULT WITH BATCHING:

------------------------------------------------------------
Server listening on TCP port 5001
TCP window size: 85.3 KByte (default)
------------------------------------------------------------
[  4]  0.0-10.0 sec    357 MBytes    299 Mbits/sec
[  5]  0.0-10.1 sec    418 MBytes    347 Mbits/sec
[  4]  0.0-10.0 sec    408 MBytes    342 Mbits/sec
[  5]  0.0-10.0 sec    422 MBytes    353 Mbits/sec
[  4]  0.0-10.1 sec    436 MBytes    362 Mbits/sec
[  5]  0.0-10.0 sec    416 MBytes    348 Mbits/sec
[  4]  0.0-10.0 sec    431 MBytes    361 Mbits/sec

Well, it's nice ?

Laurent
-- 
------------- Lau...@bu... ---------------
"The best way to predict the future is to invent it."
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