IEPM

Bulk Throughput Measurements - Rice


Bulk Throughput Measurements | Bulk Throughput Simulation | Windows vs. streams | Effect of load on RTT and loss | Bulk file transfer measurements

Rice to SLAC

On October 3, 2001, measurements were made between from hoss.ece.rice.edu to pharlap.slac.stanford.edu. Hoss was a Sun 2 *400MHz processor running Solaris 5.7 with a 100Mbps NIC located at Rice University in Houston. Pharlap was a Sun E4500 with 6*336MHz cpus and a GE interface running Solaris 5.8. SLAC had a 1Gbps link to the Stanford campus and from there a 622Mbps link to CalREN and Internet 2. The routes  in both directions uses Internet 2. The ping response for 114 default length (64 Bytes) from SLAC to Rice was min/avg/max (std) = 43.9/60.1/183 (std = 28.6). The pipechar from SLAC to Rice was also recorded. The window buffer sizes on pharlap are shown below:
ndd /dev/tcp tcp_max_buf = 4194304
;ndd /dev/tcp tcp_cwnd_max = 2097152
;ndd /dev/tcp tcp_xmit_hiwat = 16384
;ndd /dev/tcp tcp_recv_hiwat = 24576

The window buffer sizes on hoss are shown below:
ndd /dev/tcp tcp_max_buf = 1048576
;ndd /dev/tcp tcp_cwnd_max = 262144
;ndd /dev/tcp tcp_xmit_hiwat = 8192
;ndd /dev/tcp tcp_recv_hiwat = 8192

The performances shows that the maxima (the top 10% measurements) achieve over 30Mbits/s throughput. One can obtain the maxima with a single stream with a window size of 512KBytes or more. 


Created October 19, 2001, last update October 19, 2001.
Comments to iepm-l@slac.stanford.edu