Dissapointing performance of ciss RAID 0+1 ?

[Ivan Voras]

Pete French wrote:
>> You might be able to speed up the read by playing with the vfs.read_max 
>> sysctl (try 16 or 32).
> 
> Wow! That makes a huge difference, thanks. Should this not be in 'man tuning' ?

AFAIK vfs.read_max will only influence sequential reading - it's the 
readahead size. Also, it's still unexplained how increasing it yields 
performance better than that of 'dd' on a raw device.