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2 separate hard drives for read and write?

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July 17, 2006 10:55:23 AM

I read a test system config in Tom's Hardware guide which uses 2 separate hard drives for read and write. How is it done, what type of drives should I use, and what are the advantages?
July 17, 2006 11:14:47 AM

Quote:
I read a test system config in Tom's Hardware guide which uses 2 separate hard drives for read and write. How is it done, what type of drives should I use, and what are the advantages?


Uhh...what?

You mean that one drive is for reading data and one is for writing data? Such a configuration can't exist. You can't read data that hasn't been written, and you can't write data and expect another drive to read it.

If you could provide a link to what you are talking about, please do so. You're not making any sense.
July 17, 2006 11:33:32 AM

Quote:
I read a test system config in Tom's Hardware guide which uses 2 separate hard drives for read and write. How is it done, what type of drives should I use, and what are the advantages?


What YourmothersAnAstronaut said, Not possible. It sounds like you may be talking about RAID, Redundant Array of Independent (or Inexpensive) Disks which is a method of using multiple HDDs simultaneously, in different modes.

Mirroring: A back up method that writes the same data to multiple drives simultaneously. No performance increase, used for data security.

Stripping: A speed increasing method that increases system (not individual HDD) data write rate by splitting data between multiple HDDs
The bad thing about this is that if one of your HDD's dies, you lose all the data on the rest of the drives as well.

There are some other modes I know of, which arent worth mentioning here
Related resources
July 17, 2006 11:42:20 AM

At best guess he means a RAID array. The wording isnt the best, it has to be said :D 

For that, the best thing to do would be to look around on various sites and read articles on it. Heres a link you should look at, to get an explaination of the different types...

http://en.wikipedia.org/wiki/RAID

Most homes users have a RAID 0 array, although there are a few oddballs who insist on using the other types :roll:

Have a look around for articles on RAID, I'm sure the Oh-So-Kind-And-Wonderful-Forum-People will also provide some choice links, seeing as they are all knowing and all helping :wink:

EDIT: Damnit turpit, you beat me to it!
July 17, 2006 1:07:35 PM

Quote:
Most homes users have a RAID 0 array, although there are a few oddballs who insist on using the other types :roll:


You're kidding right? Most home users don't use RAID at all. And the "other types", notably RAID 1 and RAID 5, make much more sense for most home users, who don't need and mostly wouldn't notice the RAID 0 performance advantage, but who have things like personal documents, family photos, videos etc. which they really don't want to lose, and therefore which should be stored in fault-tolerant arrays. Especially considering that practically all mobos these days will do hardware RAID 1 and hard drives are cheap as chips.
July 17, 2006 1:22:14 PM

Oh, yeah, RAID. Sorry I forgot to mention that. Anyways, RAID 0's the best? Thanks for all the info. It's very useful.
July 17, 2006 1:42:44 PM

Best as in speed, but not data protection.
July 17, 2006 1:43:01 PM

depends on what you consider best. Raid can be used to increase speed, security or both. raid 0 increases speed, but reduces security.
July 17, 2006 1:46:01 PM

well... raid 0 is the fastest type of disk array (and is usually fairly scalable performancewise, in regards to how many additional hdds youre using in the same array, and even with which raid controller youre using for the array)... ...but, technically raid 0 isnt even really raid at all (unlike raid 1, 3, 5, 6, 10, etc), since it in itself offers no form of redundancy or fault tolerance, to help prevent data loss... which is, by definition, what makes raid... raid.
July 17, 2006 1:59:37 PM

Quote:
When copying large files, or when creating a drive image
the first time, it's always best to write the output file(s)
to a second hard drive (on a different spindle).

The GHOST software, for example, is an upgrade
of the former PowerQuest DRIVE IMAGE program:
that logic traversed a partition sequentially,
beginning at the outermost track and moving
inwards i.e. starting at cylinder 0, track 0, sector 0.

If GHOST is reading from C: and writing to a
higher letter drive on the same spindle, then
the read/write heads must oscillate back and
forth between the two partitions, because
partitions begin and end on cylinder boundaries.

If GHOST is reading from C: and writing to a
higher letter drive on a DIFFERENT spindle,
then the read/write heads move smoothly
from track to track, vastly reducing the
cumulative access times for this task.

This latter approach also reduces wear and
tear on the servo mechanism that positions
the read/write heads.

If you want to treat your HDDs kindly,
when copying large files, then
read from one hard drive and
write to a different hard drive
whenever you can.

A similar result obtains if one is using a
good desktop search engine like COPERNIC:
the database being read should be on
one hard drive, and the search index
being written should be on a different hard drive,
for the same reason.


Sincerely yours,
/s/ Paul Andrew Mitchell
Webmaster, Supreme Law Library
http://www.supremelaw.org/



why!
July 17, 2006 2:16:47 PM

No, I meant why are your posts so long. It's too early for all that noise. lol
July 17, 2006 2:32:22 PM

Let me ask this, if it is 10,000 Rotations Per *Minute*, why would latency be 1 *Second*/10,000 RP*M* for A Raptor?
Those are inequal units, anyone who has gone through Geometry, Trigonometry, or Chemistry would know you can't divide like that.
July 17, 2006 2:34:18 PM

well noticed! the correct would be: 1/(10,000/60)
July 17, 2006 4:25:26 PM

Quote:
Don't spit on teachers: it's very bad form.


Sincerely yours,
/s/ Paul Andrew Mitchell
Webmaster, Supreme Law Library
http://www.supremelaw.org/


And you would be the teacher? Right, CTRL-C another post.
July 17, 2006 5:48:10 PM

Quote:
Stripping: A speed increasing method that increases system (not individual HDD) data write rate by splitting data between multiple HDDs

I can't believe no one else noticed this. Stripping huh? :D 
July 17, 2006 5:50:35 PM

Well technically... stripping increases your system as well! :lol: 
Only when there is one HDD though :D 
July 18, 2006 5:48:04 AM

So, can I use RAID on any type of hard drive?
July 18, 2006 10:46:58 AM

faint................i've never heared this news

but i think 2 HDs for RAID 0 will not performance worse.....
July 18, 2006 11:49:52 AM

Yes, you can use any type of hard drive for RAID, you'll just want to check to make sure your motherboard supports it. And it's generally a good idea to use two identical hard drives for your RAID set-up, although you don't have to.

Quote:
CableTwitch wrote:
Most homes users have a RAID 0 array, although there are a few oddballs who insist on using the other types

You're kidding right? Most home users don't use RAID at all.

It's pretty clear that cabletwitch meant of the home users that have RAID, most go for RAID 0. You're right though, most home users don't even have a clue what RAID is :) 
July 18, 2006 12:12:28 PM

Quote:
You're kidding right? Most home users don't use RAID at all.


Whoops, forgot to elaborate. What I MEANT was 'most home users who HAVE a RADI array tend to use RAID0'.

Hope that clears it up a bit
July 18, 2006 1:50:31 PM

Hello all!
I thought I would join, and post. I am a fixture on some 'other' tech forums, and long-time lurker at Tommy's.

Forget RAID for just a moment...
As SupremeLaw has noted, 2 harddisks (on separate controllers) are important for several reasons.
In working with large (ie. video) files, for example transcoding MPEG2 to MPEG4 AVI, the first HD reads and the second writes.
Surely everyone can appreciate the increase in speed and reduction of wear & tear and heat, with this setup.
Or would you prefer 1 large HD, to both read the VOBs and write the 700MB output simultaneously? That's ~2 hours of harddisk hell :^)
Better to have 2 - 100GB HDs than 1 - 250GB HD, in this context.
Similar for buddy with his giant legal files...
Also, WinXP pagefile can be moved off boot partition - therefore rig can read/write to OS & programs and read/write to pagefile simultaneously.
I agree, as noted a RAID array of Striping (for speed) makes no sense for any home user... if it did then I would have one, LoL ;^)
Well maybe for the bravest and most speed-hungry - but important to have some Parity. (What's that, RAID 5?)
Best regards to all,
Jimmy 'the OGS'
Toronto
July 18, 2006 4:25:27 PM

Hmmm, that actually seems to make a lot of sense!

I wish I had thought of that before when I was divxing all my movies... What kind of speed increase would you say you might see from using this approach, if any? Anyone know of any testing or benchmarking done on this?
July 18, 2006 7:03:27 PM

Quote:
any testing or benchmarking done on this?

LoL, I've got ~200 XviD backups on a giant SATA2 drive - it's well tested ;^)
I actually have 3 drives that I work between: I will have AVI (video) on 1 HD, AVI (audio) on a 2nd HD, and mux the final AVI to the huge 3rd HD (which still is getting kinda full...)
My Windows Disk Management identifies each HD as Boot, System, and Page File - but for many folks, this is all one HD.
Benchmarking? Try it - it's not so much the speed (though it is faster) but it's just so much easier on equipment, less noise/heat too.
Try copying a 700MB file from 1 HD to itself (same HD, different folder).
Then copy the same file to another HD on another controller. About 1/2 the time! If you copy master-to-slave, it is the same as to itself.
Note: This is important for burning, too - make sure your HD with files to be burned, and your burner, are on separate controllers (ie. not master/slaved). This is one of the giant advantages of SATA that people don't always talk about...
Used to be, if you had 2 HDs and your burner was slaved to 1 of them, you had to remember how it was hooked up so that you were burning from the HD on the other controller. But, these days thank goodness - that's no longer a problem!
L8R
July 18, 2006 7:45:53 PM

So since each SATA drive has it's own connection, that means that even if both drives are on the same controller technically, it should work?

For example, on my mobo I have a nForce SATA controller and a Silicon Image SATA controller. Since the nForce has 4 connections and the Silicon Image has 2 does that mean that I kind of have 6 controllers? Or so I need to copy from the nForce to the Silicon Image or vice versa?

Hopefully some of that makes some sense.
July 18, 2006 7:54:08 PM

No, don't worry - each SATA connection is its own 'controller' with its own bandwidth.
I know what you're describing, 4 x SATA show up on 2 controllers in Device Manager, but it's different, not like PATA IDE.
July 18, 2006 8:06:13 PM

Hmm, I wonder what kind of performance difference I would see in encoding video if I went from my RAID 0 setup to this read-write approach. Any experience or even speculation on that?
July 18, 2006 9:18:08 PM

Do you not have any other drive besides your RAID array? Your rig starts from it, System Partition (boot.ini, ntldr), and everything? That's very brave.
Harddisks are extremely inexpensive - you could keep your array, and add a new 250GB/16MB (third HD) for what, $89 bucks?
You would then have effectively 2 drives to work with.
Otherwise, yes I would break the array! I would not do RAID unless I had 3 HDs minimum (personally, not even then...)
RAID in software is serious OS performance hit, unless 100% supported in hardware with the controllers.
I have seen many people completely thrilled & happy to get rid of their array. Sometimes miraculously solves strange problems/instability, too :^)
L8R
July 19, 2006 1:10:26 AM

Still can't make that RAID thing work on my PC. My motherboard manual (PC Partner P4M800Pro) says it supports RAID. I even installed the drivers and programs associated with RAID, but still no RAID. I'm just curious since I haven't tried messing around with RAID yet. Sounds very intreresting. By the way, I have 2 identical IDE hard drives, both are 80GB. Should I have bought SATAs instead?
July 19, 2006 12:34:07 PM

I do have a very old and slow WD 200gb hard drive, but I have two raptors in RAID and I'd much rather try reading from one and writing to the other than using my WD to try it out.

Still, my comp is rock solid and very speedy and I don't think I'll be encoding much video again for a while. So until then I'll just keep this info in the back of my mind.

turs, I haven't done RAID with two IDE drives but you can definitely do it. I don't think SATA would make much of a difference. You'll need to reinstall windows and enable RAID during your installation to get it to work properly. Your mobo should have directions on how to install RAID during windows installation.
!