SAS Raid - mfi driver

[Ivan Voras]

Fredrik Widlund wrote:
> Ivan Voras wrote:
>> Several:
>>
>> - are there cache differences between the controllers (amount of
>> memory, cache policy)?
> Default settings on both.

Maybe you should check what the defaults are :) Especially the amount of 
memory and is there a battery to back the cache.

>> - how does writing directly to the device (bypassing file system)
>> compare?
> Drives are four seagate 7200.10 400GB in a Raid-5 configuration.
> 
> [/mnt/test (/dev/mfid0p1 mounted)]
> read: 200MB/s
> write: 15MB/s
> 
> [/dev/mfid0p1]
> read: 200MB/s
> write: 8MB/s
> 
> [/dev/mfid0]
> read: 200MB/s
> write: 10MB/s

This is bad :( The difference between p0 and raw device might indicate a 
stripe size misalignment, but the values are too low in any case.