Hi, all. I have measured a 40% to 30% decrease in CPU use (Xeon 2.4G, 512k cache) in IBM x335 with the mobo's Broadcom NIC (5703), at 80 MB/s (one port only)by going to MTU 9000 instead of the std 1500 (kernel 2.4).
Some Bcom NICs do support jumbo, others (as the one in the HP DL145/G2, Bcom 5721) do not. I have not played with interrupt coalescing, but it's supposed to help a bit, too. I did not know Bcom NICs had some offload capabilities; can you point out where to look (or am I missing the point and you - Rob - are not using Bcom?) Regards, paulo lopes > Thanks - interesting document! > > --bob > > On Nov 2, 2006, at 11:37 AM, Robert Latham wrote: > >> On Thu, Nov 02, 2006 at 10:59:51AM -0600, Robert Olson wrote: >>> The nodes in my cluster have dual Gig-E nics (tigon3). I'm pondering >>> the installation of a second gigE switch to attach them all with a >>> private storage network, and run it with jumbo frames. Do you think >>> I'd see a significant performance increase with PVFS in this >>> configuration? >> >> Hi Bob >> >> We definitely expect jumbo frames to help out pvfs a lot. Ti's had >> good results on the teragrid, for example [1]. Unfortunately, I don't >> think anyone has quantified the benefit. >> >>> I'm also curious if folks have experimented with the effects of the >>> TCP segment offload stuff that is available on these NICs. >> >> Again, should help PVFS a lot, but we've got no hard data. >> >> ==rob >> >> [1] http://www.teragridforum.org/mediawiki/index.php?title=TG-11 >> >> -- >> Rob Latham >> Mathematics and Computer Science Division A215 0178 EA2D B059 8CDF >> Argonne National Lab, IL USA B29D F333 664A 4280 315B >> > > _______________________________________________ > Pvfs2-users mailing list > [email protected] > http://www.beowulf-underground.org/mailman/listinfo/pvfs2-users > -- 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 _______________________________________________ Pvfs2-users mailing list [email protected] http://www.beowulf-underground.org/mailman/listinfo/pvfs2-users
