RAID 1 vs RAID 0

[Max Waterman <davidmaxwaterman+gmane@fastmail.co.uk>]

Hi,

I've been reading a bit about RAID 1 vs RAID 0 on these pages :

<http://www.pcguide.com/ref/hdd/perf/raid/levels/single_Level1.htm>

They seem to suggest RAID 0 is faster for reading than RAID 1, and I 
can't figure out why.

Clearly, the write performance is worse for RAID 1 than RAID 0 since 
with RAID 1 that data you are writing at the same time is the same for 
both drives; but for reading, why can't the two drives be read as if 
they were a stripe.

You could even read the stripe in any 'direction'...when the RAID 1 
array has more than two disks, that would make RAID 1 *faster* than RAID 0.

ie

RAID 0
file is like this
0 1 2 3 4

can only be read in that order :
0 1 2 3 4 but

RAID 1
file is like this
A B C D E
---------
0 0 0 0 0
1 1 1 1 1
2 2 2 2 2
3 3 3 3 3
4 4 4 4 4

can be read as
A B C D E
0
   1
     2
       3
         4

or
1
   0
     3
       4
         2

or whatever...

Could it not help with small files and when not streaming?

Am I missing something?

Max.