On Thu, 5 Feb 2004, Chris Wagner wrote:
> Can you tell some more about the hard drive/ controller/ driver setup? My
> first guess is a driver or cacheing issue.
1CPU Host
-----------
Motherboard: SuperMicro
CPU: 1GHz Pentium III w/ 256k L2 cache
Disk Controller: Onboard IDE
Disks: 20GB IDE UDMA(100) x2
2CPU Host
----------
Motherboard: HP LH3000r
CPU: 850MHz Pentium III w/ 256k L2 cache x2 (Coppermine)
RAID Controller: AMI MegaRAID
SCSI Disks: 10 x 18GB
> What is the commonality between the 1-way and 2-way systems?
There is not much common: the 2-ways use SCSI MegaRAID/RAID0/5disks(on the
relevant volume. But going through again, while there is variation, it is
not to the same degree on the 2CPU hosts(only about 25%): the worst
offenders are the 1CPU Hosts.
> Do you have a host that u've *not* seen this on.
>
I forgot to mention the kernel for this test is linux-2.4.25-pre6, But on
linux 2.6.1, I see similar problem on the Sequential Block Read:
http://khack.osdl.org/stp/285814/logs/run-log.txt
Version @version@ ------Sequential Output------ --Sequential Input-
--Random-
-Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP
stp1-000 1G 8080 99 44855 29 15970 10 6272 76 38319 13 151.1 0
stp1-000 1G 8049 99 12655 8 11521 7 5810 71 26823 7 184.7 0
stp1-000 1G 8081 99 44719 29 15934 9 6515 79 40076 10 193.8 0
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> --
> REMEMBER THE WORLD TRADE CENTER ---=< WTC 911 >=--
> "...ne cede males"
>
> 00000100
>
