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.
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