Scott Weitzenkamp (sweitzen) wrote:
While we're talking about MTUs, is the IB MTU tunable in uDAPL and/or Intel MPI via env var or config file? Looks like Intel MPI 2.0.1 uses 2K for IB MTU like MVAPICH does in OFED 1.0 rc4 and rc6, I'd like to try 1K with Intel MPI. Scott
There is no mechanism for me to modify the MTU using rdma_cm so whatever is returned in the path record is what you get with the OpenIB-cma provider. However, you could use the OpenIB-scm provider which is hard coded for 1K MTU as a comparision. Can you run with "-genv I_MPI_DAPL_PROVIDER OpenIB-scm" on your cluster?
-arlin
------------------------------------------------------------------------ *From:* [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] *On Behalf Of *Scott Weitzenkamp (sweitzen) *Sent:* Thursday, June 08, 2006 4:38 PM *To:* Tziporet Koren; [EMAIL PROTECTED] *Cc:* openib-general *Subject:* RE: [openib-general] OFED-1.0-rc6 is available The MTU change undos the changes for bug 81, so I have reopened bug 81 (http://openib.org/bugzilla/show_bug.cgi?id=81).With rc6, PCI-X osu_bw and osu_bibw performance is bad, and PCI-Eosu_bibw performance is bad. I've enclosed some performance data, look at rc4 vs rc5 vs rc6 for Cougar/Cheetah/LionMini.Are there other benchmarks driving the changes in rc6 (and rc4)? Scott WeitzenkampSQA and Release Manager Server Virtualization Business Unit Cisco Systems*OSU MPI:* · Added mpi_alltoall fine tuning parameters · Added default configuration/documentation file $MPIHOME/etc/mvapich.conf· Added shell configuration files $MPIHOME/etc/mvapich.csh , $MPIHOME/etc/mvapich.csh· Default MTU was changed back to 2K for InfiniHost III Ex and InfiniHost III Lx HCAs. For InfiniHost card recommended value is: VIADEV_DEFAULT_MTU=MTU1024 ------------------------------------------------------------------------ _______________________________________________ openib-general mailing list openib-general@openib.org http://openib.org/mailman/listinfo/openib-general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
_______________________________________________ openib-general mailing list openib-general@openib.org http://openib.org/mailman/listinfo/openib-general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
