[RFC] virtio: use mandatory barriers for remote processor vdevs

[akong@redhat.com (Amos Kong)]

On 19/12/11 10:41, Benjamin Herrenschmidt wrote:
> On Mon, 2011-12-19 at 10:19 +0800, Amos Kong wrote:
>
>> I tested with the same environment and scenarios.
>> tested one scenarios for three times and compute the average for more
>> precision.
>>
>> Thanks, Amos
>>
>> --------- compare results -----------
>> Mon Dec 19 09:51:09 2011
>>
>> 1 - avg-old.netperf.exhost_guest.txt
>> 2 - avg-fixed.netperf.exhost_guest.txt
>
> The output is word wrapped and generally unreadable. Any chance you can
> provide us with a summary of the outcome ?
>
> Cheers,
> Ben.

Hi Ben,

The change of TCP_RR Throughput is very small.
external host -> guest: Some of throughput of TCP_STREAM and TCP_MAERTS 
reduced a little.
local host -> guest: Some of throughput of TCP_STREAM and TCP_MAERTS 
increased a little.


About compare result format:
---------------------------
>> 1 - avg-old.netperf.exhost_guest.txt

average result (tested 3 times) file of test 1
>> 2 - avg-fixed.netperf.exhost_guest.txt

average result file of test 2
>>
>> ======
>> TCP_STREAM

^^^ protocol

>>       sessions| size|throughput|   cpu| normalize|  #tx-pkts| #rx-pkts| #tx-byts|  #rx-byts| #re-trans| #tx-intr|  #rx-intr|  #io_exit|  #irq_inj|#tpkt/#exit| #rpkt/#irq
>> 1            1|   64|   1073.54| 10.50|       102|  ....

^^^ average result of old kernel, start netserver in guest, start 
netperf client(s) in external host

>> 2            1|   64|   1079.44| 10.29|       104|  ....

^^^ average result of fixed kernel

>> %             |  0.0|      +0.5|  -2.0|      +2.0|  ....

^^^ augment rate between test1 and test2

--------
sessions: netperf clients number
size: request/response sizes
#rx-pkts: received packets number
#rx-byts: received bytes number
#rx-intr: interrupt number for receive
#io_exit: io exit number
#irq_inj: injected irq number


Thanks, Amos.