There is some helpful stuff here on the tuning side: http://sources.redhat.com/cluster/wiki/FAQ/GFS#gfs_tuning -b ----- "Bob Peterson" <rpeterso@xxxxxxxxxx> wrote: > ----- "Kevin Maguire" <kmaguire@xxxxxxx> wrote: > | Hi > | > | We are running a 20 node cluster, using Scientific Linux 5.3, with > a > | GFS > | shared filesystem hosted on our SAN. Cluster nodes are dual core > units > | > | with 4 GB of RAM, and a standard Qlogic FC HBA. > | > | Most of the 20 nodes form a batch-processing cluster, and our users > | are > | happy enough with the performance they get, but some nodes are used > > | interactively. When the filesystem is under stress due to large > batch > | > | processing jobs running on other nodes, interactive use becomes > very > | slow > | and painful. > | > | Is there any tuning I (the sysadmin) can do that might help in this > > | situation? Would a migration to gfs2 make a difference? Are all > nodes > | > | treated identically, or can hosts mounting the filesystem have any > | kind of > | priority/QoS? Which tools could I use to track down any > bottlenecks? > | > | In theory we could update kernel+gfs bits to a later release, > though > | we > | saw the same issues when using the same cluster with a SL4.x stack, > | but > | for now it's > | > | kernel-2.6.18-128.1.1.el5.i686 > | kmod-gfs-0.1.31-3.el5.i686 > | gfs-utils-0.1.20-7.el5.i386 > | gfs2-utils-0.1.53-1.el5_3.1.i386 > | > | Thanks for any help/suggestions, > | Kevin > > Hi Kevin, > > We recently identified a slowdown in RHEL5.x that involves DLM > traffic. > There is a patch to speed dlm up, and it's being tested now. The > patch is built into RHEL5 kernels starting with 2.6.18-232 and newer. > That means it is currently scheduled to be released in RHEL5.6. > > It's also being z-streamed back to 5.5.z, but I don't know when that > is scheduled to go out. Unfortunately, since the problem was > opened by a customer, the bugzilla record is private to protect the > customer's confidential information. The patch is public though. > If you are a Red Hat customer, you can probably call Red Hat Support > and ask to be put on the list for bugzilla bug 604139 and > maybe find out when the fix will be available. > > There is no guarantee this is what your problem is, and there is > no guarantee that the patch will speed you up. But it might be. > > Regards, > > Bob Peterson > Red Hat File Systems > > -- > Linux-cluster mailing list > Linux-cluster@xxxxxxxxxx > https://www.redhat.com/mailman/listinfo/linux-cluster -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
