Hi everyone, I've been doing some tests with a clustered GFS installation that will evetually host an application that will make heavy use of concurrent writes across nodes. Testing such a scenarios with a script designed to simulate multiple writers shows that add I add writer processes across nodes, performance drops off. This makes some sense to me, as the nodes need to do more complicated neogtiation of locking. Two questions: 1) What is the expected scalability of GFS for many writer nodes as the number of nodes increases? 2) What kinds of things can I do to increase random write performance on GFS? I'm even interested in things that cause some trade-off with read performance. I've got the filesystem mounted on all nodes with noatime,quota=off. My filesystem isn't large enough to benefit from reducing the number of resource groups. It looks like drop_count for the dlm isn't there anymore. I looked at /sys/kernel/config/dlm/cluster - what do the various items in there tune, and which can I try to mess with to help write performance? Finally, I don't see any sign of statfs_slots in the current gfs2_tool gettune output. Is there an equivalent I can muck with? -- Ross Vandegrift ross@xxxxxxxxxxx "The good Christian should beware of mathematicians, and all those who make empty prophecies. The danger already exists that the mathematicians have made a covenant with the devil to darken the spirit and to confine man in the bonds of Hell." --St. Augustine, De Genesi ad Litteram, Book II, xviii, 37 -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
