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.