Re: Building a fast pc (1)

"Martin (news.tele.dk)" wrote:
> 
> Building a fast pc (1)
> 
> We'r trying to build a fast pc (w2k) for GIS (Geographcal Information Systems). We'r 
> looking at RAID 0, since data is allready backed up, and Speed is 1'st priority. We 
> are going for a Ultra320 RAID, but might fall back on a SATA RAID.
> 
> My question: Which is faster, 2x73Gb discs or 4x36Gb disks?

    Back-of-the-envelope analysis: For a "random" (as opposed
to sequential) I/O load, the slowest part of the I/O path is the
disk access arm.  Hence, spreading the load across four access
arms instead of two will almost certainly be faster.

    Details like the relative frequency of reading and writing,
the size and nature of NVRAM caches (if any), the O/S' attempts
to optimize the I/O (for example, by pre-fetching) can alter
the picture substantially.

-- 
[EMAIL PROTECTED]