Re: Two identical systems, radically different performance

This is driving me crazy.  A new server, virtually identical to an old one, has 50% of the performance with pgbench.  I've checked everything I can think of.

The setups (call the servers "old" and "new"):

old: 2 x 4-core Intel Xeon E5620
new: 4 x 4-core Intel Xeon E5606

both:

  memory: 12 GB DDR EC
  Disks: 12x500GB disks (Western Digital 7200RPM SATA)
    2 disks, RAID1: OS (ext4) and postgres xlog (ext2)
    8 disks, RAID10: $PGDATA

Exact same model of disk, same on-board cache, same RAID-card RAM size, same RAID strip-size, etc.??

Cheers,
Steve