[CentOS] Re: A question about RAID and partitions

[Miguel Medalha]

> If you only have 2 drives there's not much you can do to avoid concurrent 
> access.  The killer is head seek time - if you have your only 2 drives 
> tied together in any kind of raid and the head needs to be in 2 places at 
> once it doesn't matter much how you laid out the partitions. Reads can be 
> sort-of independent on raid1 but writes make both seek to the same place.
>
That's not what I was referring to. I meant, for example, that if you have 
on the same disks a RAID-0 containing data that is very frequently used and 
a RAID-1 containing data that is rarelly accessed, then you still beneffit 
from the qualities of both  RAID types despite them being on the same 
physical disks.