Re: How can i measure How long does it take to send packet of certain size?

Rick Jones (raj@cup.hp.com)
Sat, 10 Jul 1999 8:10:18 PDT

>
> I am trying to find out how long does it take to send packet by using
> follwing command line .
> cliensite> netperf -c -l -1024 -t TCP_STREAM -H <IP ADDRESS> -P 10021 -- -s
> 1028 -S 1028
>
> I am suppose to ge time it take to send packet to remote host, I am
> not getting any info about time. If you any thing about thsi please
> reply me . I would appriciate your help.

What "time" are you looking to find? Wall-clock time, or CPU time?
None of the netperf tests are set-up to (directly) measure the
unidirectional time it takes to send a packet from netperf to
netserver. That would require smarts that netperf just does not
have. (and perhaps some rather well-synchronized clocks as well...)

One can make a decent first-order approximation of the wall-clock time
by using the netperf TCP_RR test. Take the transactoin rate, invert
it, and then divide by two. This assumes symmetry which may not be
there in anything other than a simple topology, but it would be a
start.

If you meant CPU time, then you want to enable CPU utilizatoin
measurements, and then start doing some arithmatic with the serice
demands.

rick jones