Re: tainted warnings with tcp splicing in 3.7.1

Rick Jones
2013-01-10T18:22:28Z

On 01/10/2013 08:20 AM, Eric Dumazet wrote:
> I also want to thanks Rick, as the latest netperf has splice() support.
>
> Thanks Rick !

You are quite welcome - and thank you for helping me get it to actually
work :)

Those wishing to try it themselves should grab the top-of-trunk netperf
bits from http://www.netperf.org/svn/netperf2/trunk . The use of
splice() is gated by a test-specific -V option:

raj@tardy:~/netperf2_trunk/src$ ./netperf -t omni -- -d recv -V
OMNI Receive TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to
localhost.localdomain () port 0 AF_INET : copy avoidance : demo
Remote Local Remote Elapsed Throughput Throughput
Send Socket Recv Socket Send Time Units
Size Size Size (sec)
Final Final
1661688 4194304 16384 10.00 26103.14 10^6bits/s

You should see that "copy avoidance" appearing in the test banner. It
will also "take" for things like a migrated TCP_mumble test. For those
cases where you don't see a throughput change, enabling CPU utilization
measurement and looking at that and service demand should show a difference.

happy benchmarking,

rick jones