On Tue, Jan 13, 2004 at 03:31:29PM +0000, Neil Harris wrote:
== Not all disks are equal ==
Consider buying the disks specifically by access time statistics. In
particular, high-performance SCSI disks should greatly out-perform IDE
for random seek access patterns, even though their performance may be
roughly the same for data streaming. SCSI command tagging will further
increase performance, where there is concurrency on a single spindle.
See
http://www.storagereview.com/php/benchmark/bench_sort.php for some
interesting stats:
* a Fujitsu MAS3735 has an average read access time of 5.6ms, for a
price of $700 for 73 GB.
* a Hitachi Deskstar 7K250 has an average read access time of 12.1ms,
for a price of $250 for 250 GB
* a seagate U6 has an average read access time of 20.0ms, for a price of
??? for 80 GB
Also, it should be noted that if we want to extend the usefulness of
current machines, there are some 10K Western Digital IDE drives
(basically SCSI drives with an IDE interface). They have an average read
access time of 8.3ms (the WD740GD does, at least), and is $260 from
Newegg for the same size (74GB). It also has a built-in PATA-to-SATA
bridge, so it supports hot-swapping and command queueing.
--
Nick Reinking -- eschewing obfuscation since 1981 -- Minneapolis, MN