Hard drive delima

Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

Raptors are nice, but they have far too little space for the price. I
guess I'll try to 8MB drives. What's the recommended strip size?

Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

Ed Coolidge wrote:

> I was thinking about getting one of the new 16MB cache hard drives, but
> then I noticed that it would cost about the same to setup a RAID of the
> same size with
> 2 8MB cache hard drives. One of the goals of my new PC is for video
> capture and editing, so which would be better?

Drive cache only really helps when you are looking at burst file access.
Sustained transfer as you would need for video editing will not be
significantly improved by a bigger cache.

I'd look at either performance optimised RAID or high end high performance
drives (like the WD Raptor series) or a combination of the two.

Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

semi_charm@yahoo.com wrote:

> Raptors are nice, but they have far too little space for the price. I
> guess I'll try to 8MB drives.

Tis true the price/capacity ratio on Raptors is a little on the poor side,
but they are blooming fast (real world fast as well not just on paper) I
guess it depends on where your priorities lie.

> What's the recommended strip size?

The optimum stripe size can vary depending on a number of factors.

This include average file sizes, drive format, drive performance and cache,
sector size etc.

I have heard (in relation to RAID 5 and 50) that a good starting point is to
take your average file size divide this by the number of drives in your
array minus one to allow for the parity drive. When calculating this for
RAID 50 you should only count the drives in one mirror.

But personally I don't hold with this theory as if for example you have a
handful of very large files and the rest are tiny then your average gets
pushed up too high and you end up with a stripe size that is so large that
small file performance is going to really suffer.

I'd say as a rule of thumb. If you are going to be dealing with mostly large
files then set the stripe size at >512KB. If you are going to be doing a
mix then somewhere in the 128-256KB seems reasonable and if you are dealing
with lots of tiny files then perhaps go lower.

Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

I neglected to mention that if you intend to run your operating system from
the array then you need to be really carefull setting the stripe size too
large. Operating systems usually involve lots of small files (libraries
etc) and you can slow down the operating system in the quest for large file
performance.

Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

Wayne Stallwood wrote:
> I neglected to mention that if you intend to run your operating system from
> the array then you need to be really carefull setting the stripe size too
> large. Operating systems usually involve lots of small files (libraries
> etc) and you can slow down the operating system in the quest for large file
> performance.
>
Um. Yes I plan to have the OS, personal files and everything else on the raid
(I don't plan on getting a non-raided drive just for OS). I guess I'll have to
find a happy medium.