Re: Low performace of SCSI writes.
Oscar Levi (elf@buici.com)
Mon, 10 May 1999 14:20:36 -0700
On Mon, May 10, 1999 at 04:00:14PM +0200, Juan Piernas Cánovas wrote:
> Hi!
> I have problems with a SCSI hard disk. The program Bonnie gives me this
> results:
>
> -------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
> 300 4712 66.2 4584 6.1 3786 10.6 6897 92.0 14052 14.1
> 549.0 4.5
>
> My hardware components are:
>
> * Mainboard: ASUS P2B-DS ACPI BIOS Revision 1008
> * SCSI controller: Adaptec AIC-7890 SCSI BIOS v2.01 (built in
> motherboard)
> * SCSI hard disk: Fujitsu MAC3045SC Fast/Ultra-SE.
>
> I have tried kernels 2.2.5 and 2.2.6 with driver raid0145-19990421. My
> distro is RedHat 6.0.
That's a very poor performance. The first thing to do is check the
specs on the drive. What's the spindle speed and what's the average
number of sectors per track. From this you can make a guess about the
likely throughput. It is possible that 4.5MB/s is the limit on that
piece of hardware. If you find that the limit should be more like
10MB/s, check the configuration of the SCSI controller in the bios.
Also, look at the /proc/scsi data. I think I have a motherboard with
similar specs and I get 10MB/s from Quantum VikingII drives, 35MB/s in
a 4 drive RAID configuration.
-O
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/