From: [EMAIL PROTECTED]
Date: Thu, 2 Mar 2000 01:19:29 -0500 (EST)
Those are some disappointing numbers. I've got:
***** DAC960 RAID Driver Version 2.2.4 of 23 August 1999 *****
Copyright 1998-1999 by Leonard N. Zubkoff <[EMAIL PROTECTED]>
Configuring Mylex DAC960PTL1 PCI RAID Controller
Firmware Version: 4.07-0-29, Channels: 1, Memory Size: 8MB
... 5 of the following drives in a u2w hot swap system
0:0 Vendor: IBM Model: DNES-309170Y Revision: SA30
Serial Number: AJGN8615
Disk Status: Online, 17915904 blocks, 1 resets
Logical Drives:
/dev/rd/c0d0: RAID-5, Online, 71663616 blocks, Write Thru
PIII-500, 256mb, AcceleRAID 250
-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
1024 6766 85.3 9150 7.6 6452 11.9 7840 94.8 26361 13.0 268.0 2.5
I wonder how much better your numbers would be with more drives on
the DAC1164P. I just noticed the 1 resets above (on all the drives).
This box isn't in production yet. I'll have to look into that and see
if there's a problem.
An occasional reset is not a problem; it simply means a command timed out and
the DAC960 firmware responds by resetting the bus and retrying all the pending
commands. In the case of the IBM drives, there is a mode page setting that
controls how long a command is allowed to remain before completion, and I've
seen the default on drives sometimes set to unlimited. It's best to set this
to 5 seconds or so since the DAC960 timeout is 6 seconds. I don't recall
offhand the location of these parameters in the mode pages, but the IBM disk
drive documentation and their utilities know.
Leonard
