On Thu, Jul 14, 2005 at 12:33:30PM -0600, Andreas Dilger wrote: > On Jul 13, 2005 17:12 -0700, Jeffrey W. Baker wrote: > > I'm setting up a new file server and I just can't seem to get the > > expected performance from ext3. Unfortunately I'm stuck with ext3 due > > to my use of Lustre. So I'm hoping you dear readers will send me some > > tips for increasing ext3 performance. > > > > The system is using an Areca hardware raid controller with 5 7200RPM > > SATA disks. The RAID controller has 128MB of cache and the disks each > > have 8MB. The cache is write-back. The system is Linux 2.6.12 on amd64 > > with 1GB system memory. > > > > Using bonnie++ with a 10GB fileset, in MB/s: > > > > ext3 jfs xfs > > Read 112 188 141 > > Write 97 157 167 > > Rewrite 51 71 60 > > > > These number were obtained using the mkfs defaults for all filesystems > > and the deadline scheduler. As you can see JFS is kicking butt on this > > test. > > One thing that is important for Lustre is performance of EAs. See > http://samba.org/~tridge/xattr_results/ for a comparison. Lustre > uses large inodes (-I 256 or larger) to store the EAs efficiently. > > > Next I used pgbench to test parallel random I/O. pgbench has > > configurable number of clients and transactions per client, and can > > change the size of its database. I used a database of 100 million > > tuples (scale factor 1000). I times 100,000 transactions on each > > filesystem, with 10 and 100 clients per run. Figures are in > > transactions per second. > > > > ext3 jfs xfs > > 10 Clients 55 81 68 > > 100 Clients 61 100 64 > > > > Here XFS is not substantially faster but JFS continues to lead. > > > > JFS is roughly 60% faster than ext3 on pgbench and 40-70% faster on > > bonnie++ linear I/O. > > This is a bit surprising, I've never heard JFS as a leader in many > performance tests. Is pgbench at all related to dbench? The problem > with dbench is that for cases where the filesystem does no IO at all > it reports a best result. In real life the data has to make it to > disk at some point. JFS tends to lead in two areas, low cpu utilization compared to other filesystems, and on a new filesystem, layout is generally very good. The low CPU utilization helps in environments where you have a lot of filesystems or just a lot of I/O going on, we've seen on SPEC SFS that JFS tends to be the best because of that. (Yes, SPEC SFS is a rather crazy workload, but then so are a lot of other common ones) JFS's main weak point is on meta-data intensive workloads (like dbench) because of deficiencies in the logging system and some poorly placed synchronous operations which are currently being tackled. We've also been slowly pushing in changes to improve JFS performance, some of them have made it into 2.6.12. Sonny _______________________________________________ Ext3-users@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/ext3-users
