On Mar 09, 2009 13:57 -0400, Michel Dionne wrote: > The sgi has 256 dual core 1.6Ghz cpus.
Is this considered a single system (e.g. there are 256 entries in /proc/cpuinfo) or is this a cluster of nodes? The client SMP scalabilty fix is only really significantwhen there are 8+ cores on a node. > The write performance is up to 375MB/s on a single dd using 1 core and > writing on a folder with lfs setstripe of 4. > It is only on read that the cpu usage of this one core limits reads to > 142MB/s. This core is busy with ptlrpcd during the read. > Is version v1_8_0_RC2 production ready or should we wait? The v1_8_0_RC2 is just a release candidate, and has since been replaced by v1_8_0_RC4, which is currently undergoing testing. There aren't expected to be serious problems remaining at this stage of testing, but this is not yet a fully supported release so I would only advise using it for testing. The SMP locking fixes previously referenced are only needed on the client node, so if you have a time where you can do testing with the RC4 code this will tell you if the read locking is the problem. > -----Original Message----- > From: [email protected] [mailto:[email protected]] On Behalf > Of Andreas Dilger > Sent: March 6, 2009 05:07 > To: Michel Dionne > Cc: [email protected] > Subject: Re: [Lustre-discuss] read performance on ia64 > > On Mar 04, 2009 14:53 -0500, Michel Dionne wrote: > > I am running test between an X4150 and SGI Altix with luster 1.6.6 and > > I can see a read performance drop on the SGI. > > How many cores on the SGI system? > > > Numbers: > > X4150 > > dd if=/dev/zero of=/mnt/exec4_client_ib/mike/4/bigfile bs=4096k > > count=10000 (336MB/s) this a folder with a stripe of 4 for all tests > > dd if=/mnt/exec4_client_ib/mike/4/bigfile of=/dev/null bs=4096k > > (461MB/s) > > > > SGI Altix > > dd if=/dev/zero of=/mnt/exec4_client_ib/mike/4/bigfile bs=4096k > > count=2000 (371MB/s) 99% of the core is running dd > > dd if=/mnt/exec4_client_ib/mike/4/bigfile of=/dev/null bs=4096k > > (142MB/s) 20% is running dd and 80% is running ptlrpcd > > > > > > The X4140 is running: > > 2.6.18-92.1.10.el5_lustre.1.6.6smp #1 SMP Tue Aug 26 12:16:17 EDT 2008 > > x86_64 x86_64 x86_64 GNU/Linux > > Red Hat Enterprise Linux Server release 5.2 (Tikanga) > > > > The SGI is running: > > SGI Altix systems 2.6.16.46-0.12-default #1 SMP Thu May 17 14:00:09 > UTC > > 2007 4 ia64 ia64 GNU/Linux > > Please try running the v1_8_0_RC2 from CVS - it has patches that should > improve the scalability of the client when there are many CPUs. > > Cheers, Andreas > -- > Andreas Dilger > Sr. Staff Engineer, Lustre Group > Sun Microsystems of Canada, Inc. Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc. _______________________________________________ Lustre-discuss mailing list [email protected] http://lists.lustre.org/mailman/listinfo/lustre-discuss
