I can report a decrease of circa 10% CPU use per GbE link in an IBM x335 (dual Xeon 2.6GHz) with on-board Broadcom NICs and SMC switch, when going from standard 1500 to 9K frames on the netperf benchmark, at full bandwidth (circa 80MB/s).
Best Regards, paulo > Doug and Jeff have good points (and some good links). On thing to > also pay attention to is the CPU utilization during the bandwidth and > application testing. We found that on our cluster (various Dells > with built in GigE NICs) while we did not see huge differences in > effective bandwidth, the CPU overhead was notably less when using > Jumbo Frames. > > Again, YMMV. > > Good luck, > > -bill > -- Paulo Afonso Lopes | Tel: +351- 21 294 8536 Departamento de Informática | 294 8300 ext.10763 Faculdade de Ciências e Tecnologia | Fax: +351- 21 294 8541 Universidade Nova de Lisboa | e-mail: [EMAIL PROTECTED] 2829-516 Caparica, PORTUGAL _______________________________________________ Beowulf mailing list, [email protected] To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
