SAS Raid - mfi driver

[Fredrik Widlund]

Hi,

We have a problem with the MFI raid-driver under FreeBSD 6.1 and 6.2-PRE.

Hardware: Dell 1850
Raid adapter: LSI 8480E

There is no problem to detect, initialize and configure, but there is a
serious problem with performance with Raid-5. Read performance is good,
but write performance bottlenecks at 20MB/s. We've tried different
setups but hit the same limitation again and again. The strange part is
that a Dell raid adapter based on the same chipset, the Perc 5/I, works
well with writes achieving 200MB/s.

Any ideas would be greatly appreciated.

Kind regards,
Fredrik Widlund