Hello, 

Here are a few numbers with regards to network throughput of p9 and
other operating systems.  No substantial discussion is presented, but
we would like to draw your attention towards the small data size
transmission results.


The setup is as follows: EtherExpress100 network cards on pentuim 800s
for plan9, Netgear GA620 for the GigE tests.

The test involves:


Sender:
for(i = 1; i < somesize; i= i<<1) {
	buf = mallocz(i, 1);
	tbegin = nsec();
	for(j = 0; j < 10000; j++)
		write(fd, buf, i);
	tend = nsec();

	/* calculate and print result */
}


Receiver:
buf[8192];
dnull = open("/dev/null", OWRITE);
while((n = read(fd, buf, 8192)) > 0) 
	write(dnull, buf, n);


The same code was used for linux/fbsd but all the headers and crappy
TCP initialization crud was added in front of it.

Also, the Linux/FBSD code uses ftime(2) for calculating the elapsed
time, which gives resolutions down to a microsecond.  We found no
better way to measure elapsed time.

Note: we're currently looking at ways to improve the latency penalty
for small data size packets and suggestions are most welcome.


cheers, andrey