Re: filmscanners: RAID and scratch

[Todd Flashner <tflash@earthlink.net>]

Laurie

I don't blame you for reading me as you did. I did understand that it takes
two drives for my RAID 0. I will have four drives. When Charles said that a
RAID behaves like a single drive, I shorthanded my description of it by
referring to it as a single drive. My fault.

Allow me to attempt to clarify. What I will have is A) 27GB drive, B) 60GB
RAID 0 (using two 60GB drives), C) another 60GB drive.

The 27GB drive is probably the slowest drive, and the other three 60GB
drives will all be the same make and model (IBM Deskstar IDE). So with that
info, what is the best location for OS, Photoshop, images, backup?

Using the alphabet scheme I used above to denote my volumes, my plan was:

A) OS, Photoshop, misc.
B) Images
C) Partition for scratch, partition for backup.

Does that seem like the best way to distribute: system, application, files,
and scratch - across these three volumes for max speed? I know it's best to
have my scratch on a separate drive from the application, but I don't know
if it's best to group the OS with the app; or the app with the files; or the
OS, app, and files all together...

Todd



> I am not sure you understand how a RAID array works.  To establish either a
> RAID O or a RAID 1 you need two drives (both of the same size and model
> preferably) for either the striping or the mirroring array.  To do a RAID 0
> + 1, you would need preferably 4 drives of the same size and model, although
> you might be able to get away with having the mirroring drive be a size
> equal to the two striped drives of RAID O.  In point of fact, you can have
> only drive that would not be in the RAID array and on a non RAID controller
> which you could use to house your OS, swap files, scratch files, and maybe
> program files in one partition or in separate partitions on it if you set up
> a RAID array for your data, since the array would take two drives minimum.
> 
> -----Original Message-----
> From: owner-filmscanners@halftone.co.uk
> [mailto:owner-filmscanners@halftone.co.uk]On Behalf Of Todd Flashner
> Sent: Saturday, November 17, 2001 8:23 PM
> To: filmscanners@halftone.co.uk
> Subject: Re: filmscanners: RAID and scratch
> 
> 
> on 11/17/01 7:51 PM, Charles Knox wrote:
> 
>> In general, the RAID partition would be faster, but not by as much as you
>> might think, since it would also be creating more seeks on the primary
>> drive, thus slowing it down quite a bit.
> 
> Forgot to ask about where the system and application should go. Lets say I
> have three disks, one of which is the RAID. I was thinking to use my
> smallest drive for my OS and applications (including PS), the RAID
> exclusively for images, and a third drive for a second system, misc. backup,
> and a partition for scratch. Is this the best way to allocate system,
> images, application, and scratch, across the three drives or should they be
> grouped differently?
> 
> Todd
>