Dual Disk SATA

[Ramone]

Those numbers are not for burst speed they are for average transfer speeds.
The burst speeds are actually much higher but I pay no attention to those
numbers.

Ramone

 

[Ramone]

Those numbers are for average transfer rates, not burst speed. I pay no
attention to burst speed numbers.

Ramone

 

[John John (MVP)]

Actually the Burst rate increase would not be much better, it would be
the sustained reads and writes that benefit from having the RAID 0. If
you are doing say video editing then yes a gain would be seen. But
little files that don't exceed the the onboard cache would maybe even
drop slightly from overhead on the two drives.
http://www.anandtech.com/storage/showdoc.aspx?i=2969&p=4

Thanks for clearing that up, Bob. As you say, for video editing and the
likes there may be real gains but for most other things the difference
is negligible. The conclusion page of the same article pretty well sums
it up:

If it is not obvious by now, RAID 0 will provide outstanding results in
synthetic benchmarks but really does nothing in actual applications. We
should probably clarify that statement in detail. Utilizing the best
performing drives in RAID 0 is the setup to have if you are looking to
publish top benchmark scores with results in PCMark05 improving by 25%
as an example. That same setup will provide you with at best minimal
performance improvements in most applications, or sometimes no
difference at all.

[end qoute]
http://www.anandtech.com/storage/showdoc.aspx?i=2969&p=9

And from another article on the same site:

[Qoute]
If you haven't gotten the hint by now, we'll spell it out for you: there
is no place, and no need for a RAID-0 array on a desktop computer. The
real world performance increases are negligible at best and the
reduction in reliability, thanks to a halving of the mean time between
failure, makes RAID-0 far from worth it on the desktop.

(...)

Bottom line: RAID-0 arrays will win you just about any benchmark, but
they'll deliver virtually nothing more than that for real world desktop
performance. That's just the cold hard truth.

[end quote]

http://www.anandtech.com/printarticle.aspx?i=2101

Claims of performance increases in the 100% range are specious or
dubious to say the least!

John

 

[John John (MVP)]

It still makes little difference in the real world, these benchmark
numbers do not translate into real and equal performance gains, at best
(unless you work with really large files) the gains won't amount to
anything much more than a couple of percentage points. For most users
RAID-0 on the desktop is just not worth the added overhead and decreased
reliability.

John

 

[R. McCarty]

There is always the "Placebo Effect" with many PC operations. First &
foremost is the "Clean Install = Fast", which is mostly due to a platform
which is not fully loaded. But there is a whole group of Windows users
who follow a regular schedule of Format & Start over. RAID is just one
setup that "most" desktop users do not need - the same for setting up &
using Dynamic volumes. If the OP believes he gets a appreciable return
using RAID-0 then that's fine, but he shouldn't globally recommend it to
NG readers implying everyone will get an enormous performance gain.
Anyone can post a favorite Tweak or Setup but should at the least take
the time to mention any downside or risk with it.

I have a system with 5 SATA drives and a couple of different controllers.
I use both internal and external drives. Using DiskSpeed32, I measure an
average throughput of ~82 Megabytes-per-Sec on all of them. This is
more than enough speed.

 

[Ken Blake, MVP]

So moral of the story is with SATA, hardware RAID 0 doubles performance (as
you shown), software RAID 0 but doesn't offer very much except for a lot of
potential risk (as Ken explained)!

My personal experience was with hardware RAID. It provided no
perceptible increase in performance.