On Sat, 2008-05-10 at 09:10 +0200, Klaus Steinberger wrote: > How can I performance-tune GFS or make it any faster? (snip) > Use -r 2048 on gfs_mkfs and mkfs.gfs2 for large file systems. Actually, this is a delicate balance. If you have too many resource groups (RGs) then it spends a lot of time searching to find the one it needs, but once it finds the RG, the bitmap search will be fast. If you have fewer RGs, it will spend less time searching for the right one, but the bitmaps for each will be bigger, so it will spend more time searching the bitmap once it has been found. I've written a performance enhancement to the "bitfit" algorithm for GFS2 that increases the speed of bitmap searches, making it more speedy to use fewer RGs with larger bitmaps. That code could be back-ported to GFS, but it hasn't been done yet. Actually, there are a lot of performance improvements done for GFS2 that COULD theoretically be ported back to GFS, if someone took the time. Perhaps I'll open an RFE bugzilla and post any patches I come up with to the cluster-devel mailing list. Regards, Bob Peterson Red Hat Clustering & GFS -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
