2x 250GB serial-ATA in RAID-1

  • Thread starter Thread starter Cuzman
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Cuzman

OK, so I'm constantly updating specs for a build that will happen some time
after the new GPUs are all released. I'm looking at going RAID-1 with 2x
250GB drives, for back-up and read-speed reasons. I'll probably look at
getting 2x Western Digital Caviar SE S-ATA 250GB WD2500PD drives, but I'm
wondering what effects the reduction in write-speed has with running RAID-1.
What operations does it become noticeable or detrimental during?

http://www.storagereview.com/articles/200309/20030904WD2500JD_8.html
 
I'm not sure what you're looking for here, but obviously determining exactly
what would be affected varies greatly based on what you intend to do, what
applications are installed, etc. I use my IDE ATA 2 x WD 200GB RAID1 for
data storage, long term storage. I seriously doubt that most users would
even notice the difference between RAID1 and non-RAID1 at all, I certainly
don't. Not unless the HDs were substantially different in model, speed,
buffering, etc. Perhaps if one was 5400RPM w/ 2mb buffer and 12ms response,
the other 7200RPM w/ 8mb buffer and <9ms response, you might notice,
obviously RAID can only perform at the lesser of the two HDs. But beyond
that, unless you're benchmarking, the differences are going to be virtually
imperceptible.

I also keep my OS (and anything else I consider expendable) on two other
HDs, in RAID0 (stripping), not only negating the issue, but improving it
beyond a standalone HD! Of course, one other option is RAID0+1 (your mobo
might not support this), which provides BOTH redundancy and performance
using 4 HDs.

Let's put it this way, if you had two machines, A and B, and each was
indentical except for one being RAID1, the other NOT, and sat the same
person in front of each and asked them to tell you which one was RAID,
they'd do no better than flipping a coin! For me, that's says it all. Now,
if you're configuring this for a server, where you intend to nightly update
a database over several hours, I suppose *then* you might notice the RAID
config takes more time, maybe by a few minutes. Any situation that is
severely and inherently write-intensive is more dramatically affected, but
for the average home user, its a non issue.

HTH

Jim
 
OK, so I'm constantly updating specs for a build that will happen some time
after the new GPUs are all released. I'm looking at going RAID-1 with 2x
250GB drives, for back-up and read-speed reasons. I'll probably look at
getting 2x Western Digital Caviar SE S-ATA 250GB WD2500PD drives, but I'm
wondering what effects the reduction in write-speed has with running RAID-1.
What operations does it become noticeable or detrimental during?

http://www.storagereview.com/articles/200309/20030904WD2500JD_8.html
Click to expand...

Depends largely on the RAID card (and/or the
drivers/software). Stripe size also matters a lot
(e.g. if your average file size is 4KB, you probably
don't want a stripe size of 64KB). But picking a stripe
size is still a bit of a black art.
 
Cuzman said:
OK, so I'm constantly updating specs for a build that will happen some time
after the new GPUs are all released. I'm looking at going RAID-1 with 2x
250GB drives, for back-up and read-speed reasons. I'll probably look at
getting 2x Western Digital Caviar SE S-ATA 250GB WD2500PD drives, but I'm
wondering what effects the reduction in write-speed has with running RAID-1.
What operations does it become noticeable or detrimental during?

http://www.storagereview.com/articles/200309/20030904WD2500JD_8.html
Click to expand...

I know this is not what you asked, but I couldn't help myself. :-)

If you want safety, don't use mirrored disks...
(I know I might get flamed now, but mirrored disks only protect you against
HD-failure!)

Use one disk in your system, and an external for backup.
The additional cost for an external disk is minimal.

Your setup will NOT protect you against:
Theft, Powersurges, accidential deletion, Virus etc.

Using an external HD that is NOT attached to the system will not be affected
by lightning etc.
If you keep it in a safe place thieves might also miss it...

Then you just find time to syncronize the disks once in a while when you are
sure the original is OK.
Hopefully just a litle bit of your data changes, and the time needed should
be minimal.

Just my two cents.

Rune
 
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