[netperf-talk] Netperf network traffic generation rate

[Rick Jones]

99 times out of ten, discussions which start in netperf-talk should 
remain in netperf-talk.  And this is not that 100th time out of ten :)

On 08/20/2011 04:36 AM, Kirti mahajan wrote:
> Thanks Rick,
>   My objective is to load the 10GbE network with 10MBytes/sec traffic. I
> may be wrong, instead of UDP_STREAM I am using UDP_RR to check the
> latency of the system under this load. Perhaps after reconfiguring the
> netperf with --enable-intervals the command do the job
> netperf -H fastcontroller1 -t UDP_RR -b 1M -w 1 -- -r 1024,1024

Assuming the code to parse the -b option understands the suffix (which 
isn't a given) I believe that command will attempt to do 1 million 
transactions in one millisecond.  I don't think the system will be up to 
that...

If you want to use 1024 byte sends, and a 1 millisecond burst interval, 
then convert your 10 MByte/s goal to MB/millisecond and then 
KB/millisecond and set the burst size to be that many sends:

netperf -H fastcontroller1 -t UDP_STREAM -b <value> -w 1 -- -m 1024

and so long as the system on which netperf is running can complete the 
<value> 1024 sends in < 1 millisecond, you should be OK.

> btw in the absence of burst mode what is the rate of generation of packets?

Depends on the test and the protocol being used.  It will be some 
combination of the CPU power of the sending and receiving systems, the 
latency of the network, window sizes (if any), efficiency of the stack 
and driver(s) etc etc.

happy benchmarking,

rick jones

> Thanks and Regards
> --Kirti
> On Fri, Aug 19, 2011 at 9:39 PM, Rick Jones <rick.jones2 at hp.com
> <mailto:rick.jones2 at hp.com>> wrote:
>
>     On 08/19/2011 05:03 AM, Kirti mahajan wrote:
>
>         I am new to the netperf tool. After a quick scan of the manual I
>         am not
>         sure whether netperf can control the rate of packet generation
>         to test
>         netowork performance. Like generate 1000 packets of size 64bytes
>         at a
>         rate of 2KHz.
>
>
>     While the terminology may not match yours (eg 2KHz) I believe what
>     you seek is the functionality one gets when one includes
>     "--enable-intervals" on the ./configure command line:
>
>     ./configure --enable-intervals ...
>
>     That will enable the global '-b <burst size>' and '-w <burst
>     interval>' options which can be used to pace the rate at which
>     netperf does its thing.  By default, netperf will use the systems
>     interval timer, and so is constrained to that granularity for the
>     burst interval.  If you also include "--enable-spin" on the
>     ./configure netperf will instead sit and spin until the interval is
>     reached.
>
>     happy benchmarking,
>
>     rick jones
>
>