On Feb 11, 2007 23:51 -0800, Sridharan Ramaswamy (srramasw) wrote: > Thanks Andreas. I'll try a lower value for the num_threads=NNN. How low > can these values be?
On a very small UML system there are only 2 threads per service. > > -----Original Message----- > > From: Andreas Dilger [mailto:[EMAIL PROTECTED] > > Sent: Sunday, February 11, 2007 11:39 PM > > To: Sridharan Ramaswamy (srramasw) > > Cc: [email protected] > > Subject: Re: [Lustre-discuss] Number of processes in Lustre tunable? > > > > On Jan 23, 2007 10:39 -0800, Sridharan Ramaswamy (srramasw) wrote: > > > I'm tring to measure the overhead of having Lustre on the > > system. Among > > > other things, I noticed it starts lot of processes, > > > > > > root 4565 1 0 Jan03 ? 00:00:00 [ll_mdt_attr_14] > > > root 4636 1 0 Jan03 ? 00:00:01 [ll_ost_13] > > > root 4651 1 0 Jan03 ? 00:00:08 [ll_ost_io_13] > > > root 4550 1 0 Jan03 ? 00:00:03 [ll_mdt_14] > > > root 4516 1 0 Jan03 ? 00:00:00 [ldlm_cb_31] > > > > > > I can account about 200 processes related to Lustre on an > > OST node. That > > > seems a lot considering we would like to run other > > applications on the > > > same node. Is it possible to tune these number of processes > > down? Say > > > reduce 32 ldlm process to about 8. What kind of performance > > degradation > > > to expect if we can do that? > > > > You can reduce the MDS and OST process count via modprobe.conf: > > > > option mds mds_num_threads=NNN > > option ost ost_num_threads=NNN > > > > If this isn't good enough, you can change the count at compile time > > in lustre/include/linux/lustre-net.h > > > > In 1.6 the number of threads will be more dynamic, depending on load. > > > > Cheers, Andreas > > -- > > Andreas Dilger > > Principal Software Engineer > > Cluster File Systems, Inc. > > Cheers, Andreas -- Andreas Dilger Principal Software Engineer Cluster File Systems, Inc. _______________________________________________ Lustre-discuss mailing list [email protected] https://mail.clusterfs.com/mailman/listinfo/lustre-discuss
