Seeing as we're all using RAID here, someone might know how to eek
better performance out of a I/O subsystem.
I'm using a Dual PPro system (Tyan S1668) with 3 Mylex KT-958
controllers. Each controller has 3 Seagate Barracuda ST15150W
drives (fast/wide, approx. 5MB/sec internal transfer bandwidth).
I have all nine disks in a RAID 5 array, so I figure 15*3=45MB/sec
usable bandwidth. Raidtab has everything configured for 64k chunks.
I require fast random I/O. I was thinking about upgrading to either
all newer barracuda drives (8MB internal transfer per drive) or Cheetah's
(12MB internal transfer per drive). But my question is will these
drives give me better performance for random I/O? Anyone here have any
real-world figures?
(system has 256MB memory, CPU utilization is around 50-60% of one CPU,
kernel=
2.0.35)
-------Sequential Output-------- ---Sequential
Input-- --Random--
-Per Char- --Block--- -Rewrite-- -Per
Char- --Block--- --Seeks---
Machine MB K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU /sec
%CPU
news:md0 1000 6213 89.0 11416 50.6 4412 34.4 6813 73.3 8395 23.8 149.7
10.0
Steve
