Keywords: TechAssessWG
Jim Gray is correct - we are absolutely disk IO bound on the queries.
Today's laptop CPUs are probably fast enough now. I have always
had separate file systems for the DB and the images. DB disk IOs are
going to be smaller and variable length. Images are of constant
size. This
is a first level optimization, but far from sufficient.
Seek time will be one of our limiting factors, so Jacek and I have
discussed
allocating a portion of each disk to the DB; this can cut the average
seek time.
This approach might make sense with the 700+ GB drives of today.
To avoid wasting storage, we should explore storing infrequently
accessed
data on the remaining portion of each drive.
Here is another approach - the Fujitsu MAX3147 which, to no surprise, is
a 147 GB disk drive in the 2.5 inch form factor. The most useful
feature is
an average seek time 3.3 milliseconds. The down side is the lower
capacity.
--Don
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