topic Re: Slow Performance in Disk Enclosures

Slow Performance

Ayman Altounji — Sun, 21 Jan 2001 00:00:00 GMT

I am experiencing very low write performance.

I have a single 9G Seagate Cheetah 10k RPM SCSI drive attached to the raid controller (Raid 0 config since it is a single drive). My read performance is as I would expect - very fast, improved by cacheing. I have the cache configured as 8M read/8M write.

The write performance is pretty much 2MB/s - much lower the I get with a standard SCSI controller (about 10MB/s on the same drive)

Why is this? How can it be corrected?

Re: Slow Performance

Ayman Altounji — Mon, 22 Jan 2001 00:00:00 GMT

I have tried a 2 drive RAID 0 and a 2 drive RAID 1 configuration as well. On RAID 1 I see a read performance bursting to 39MB/s and averaging 15MB/s. Max write throughput is 2.5MB/s averaging 2.3MB/s. I see a similar poor write performance on the RAID 0 configuration.

Hooking the same drive to a standard SCSI controller yields much higher write performance.

I am using HD Tach 2.61, CLI Bench 3 and Ziff Davis Winbech 99 v1.2 for benchmarking, all the current versions. I have current array drivers. I see roughly identical performance numbers across all the benchmarks.

Re: Slow Performance

Ayman Altounji — Wed, 07 Feb 2001 00:00:00 GMT

Try firmware upgrade on the Smart 2/DH . Also upgrade the Array Controller driver .