JFS fastest filesystem for PostgreSQL?

[reposted due to delivery error -jwb]

I just took delivery of a new system, and used the opportunity to
benchmark postgresql 8.0 performance on various filesystems. The system
in question runs Linux 2.6.12, has one CPU and 1GB of system memory, and
5 7200RPM SATA disks attached to an Areca hardware RAID controller
having 128MB of cache. The caches are all write-back.

I ran pgbench with a scale factor of 1000 and a total of 100,000
transactions per run. I varied the number of clients between 10 and
100. It appears from my test JFS is much faster than both ext3 and XFS
for this workload. JFS and XFS were made with the mkfs defaults. ext3
was made with -T largefile4 and -E stride=32. The deadline scheduler
was used for all runs (anticipatory scheduler is much worse).

Here's the result, in transactions per second.

ext3 jfs xfs
-----------------------------
10 Clients 55 81 68
100 Clients 61 100 64
----------------------------

-jwb