Proliant ML370 slow performance

[Carlos Parra Lara]

In a Server Proliant ML370 G3 Xeon 3.0 GHz, with a Smart Array 641 controller 64MB Cache, 3 Hard Disk SCSI Ultra320 10K RPM 72.8 GB in RAID 5, 2GB RAM Memory and WIN2K Server SP4, configured for Database Server, a test restore DB process take 3 to 4 hours to complete, with nobody using it.
Same test process in a normal PC HP D220/P4 2.8 Ghz/IDE 80 GB/ and 256MB RAM and Win2K Server SP4, take a little more than 1 hour.
What could be happening with this sever?
Both cases was clean installations, and Proliant Server performance it is very poor.
Any idea what could be wrong?

[ernst limbrunner · Accepted solution]

i guess your other sysem does not use raid 5. writing to a raid 5 array IS EXTREMLY slow compare to 2 mirrored disks or even a single disk !!!

raid 5 is well known for very good read performance and pretty poor write performance.

and if the os and database are on the same array (even if you have 2 logical drives) things become even worse.

best regards from germany
ernesto

[Carlos Parra Lara]

Thanks for your reply Ernst, I see light now. Then I can separate one physical disk for SO y others for database, for better performance. We choose RAID 5 because RAID 0 it is more expensive (less capacity than RAID5), but maybe it is time to think again.

In Controller Smart Array 641 it is possible to expand more cache memory up to 128 MB. This expansion card could make some difference?.
It would be worth the trouble to buy it?

Saludos desde Mexico

[Igor Karasik]

Carlos, I don't think addition of cache memory to RAID controller will significantly help in your case.
Make sure you have identical SQL/windows configuration (include service pack) on both machines.
Try to run performance monitor during restore and see that happens with CPU/disks.
Did you see suggestions from similar thread:
http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=967340

[Carlos Parra Lara]

Thanks Igor, I see thread, looks like same problem, but no solutions.
Our server it is now on production, with all firmware updated, but still slow. RAID 5 good for read disk, but very slow performance for write, and good for avoid stopping server for disk failure. Maybe it is time to probe another brand of server machines :-)
Anyway, we are going to buy cache memory for RAID controller and another disk for SO.

Thanks for your help

[Ryan Goff]

Without having a BBWC module on your 641 that will slow your write performance significantly.

Write cache is good because it allows the OS to continually stream data to the controller instead of having to stop and pause for the data to be written directly to the drives.

That doesn't sound like a lot but think of it like comparing RAM to a Page/Swap File.

Having the cache enabler for this controller will help you tremendously.

[Carlos Parra Lara]

Thanks Ryan, your explanation looks good. We are going to buy cache memory module for 641. I see in another thread some programs to meter Read/Write Performance. I will make tests before and after memory upgrade to see if any increase in performance. Maybe this info could help somebody else in future.

Thanks again

[Carlos Parra Lara]

Closed thread. We can´t buy a BBWC module for Smart Array 641 controller (no more budget). Server performance is tremendously slow, because RAID 5 of SCSI Disks.