Giuseppe, I think it still makes sense to develop GAMMA for GigE. Here are some preliminary numbers I was able to achieve on a very low cost cluster (http://www.clustermonkey.net//content/view/41/33/)
The Gamma ping-pong test gives latency through the switch as (useconds): (lowest < average < highest) 9.13639 < 9.54739 < 15.5897 it also reports 72 MB/sec throughput (which is pretty good for a 32 bit/33 MHz NIC!) The netpipe TCP was 29 usec latency and 66 MB/sec. Here are some *preliminary* MPI netpipe numbers as compared to LAM and MPICH. LATENCY: http://www.clustermonkey.net/download/kronos/extra/NPmpi-latency-signature.png THROUGHPUT: http://www.clustermonkey.net/download/kronos/extra/NPmpi-netpipe.throughput_vs_blocksize.png Before I do more testing I needed to add more memory to the nodes and update some software (working on this today as a matter of fact) I did run the NAS suite without no problems. Thanks for your efforts. -- Doug > Hello, > > I'm glad to announce that GAMMA has been ported to x86-64 CPU architecture > :-) > This release of GAMMA has been tested on a GigEth cluster of dual-Xeon (32-bit) > as well as a cluster of single-EM64T (courtesy of OpenCFD, Ltd). So, we lack > (and need!) tests on GigEth cluster of dual-processor x86-64 machines (we > have no such hardware on site). > > A new, 64-bit capable, version of MPI/GAMMA has been released as well. > > GAMMA only supports the Intel PRO/1000 Gigabit Ethernet NIC (e1000 driver). > Latency at MPI level is below 12 usec, switch included (6.5 usec back-to-back). > No significant difference between 32-bit and 64-bit. > > More details at the GAMMA web page, http://www.disi.unige.it > > Some tests on computational fluid dynamics jobs (courtesy of OpenCFD, Ltd) > show a very interesting comparison between MPI/GAMMA and LAM. I will post > more details on the GAMMA web page soon. > > A question: > > Does it still make sense to have a low-latency communication library for Gigabit Ethernet? > > Bye, > > Giuseppe Ciaccio http://www.disi.unige.it/person/CiaccioG/ DISI - Universita' di Genova via Dodecaneso 35 16146 Genova, Italy phone +39 10 353 6637 fax +39 010 3536699 [EMAIL PROTECTED] ------------------------------------------------------------------------ _______________________________________________ > Beowulf mailing list, [email protected] > To change your subscription (digest mode or unsubscribe) visit > http://www.beowulf.org/mailman/listinfo/beowulf > -- Doug _______________________________________________ Beowulf mailing list, [email protected] To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
