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91mustang

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IO problems

Hello,

I am having some serious IO problems on a ML350 with 2003 running on it.

Have a Raid Controller in it  (64 mb cache). 5 drives (2 mirrored, 3 Raid 5)
Dual Xeon 3.06
We have sql server 2000 running on it, and the performance on it is terrible.

We ran a SQL server IO test on it, and my 1.6ghz laptop and the laptop beat by a factor of 5 in read/writes per second.

I had a HP employee in today, and he replaced everything but the system board and drives. No changes.

After all this he decided that the server is running fine. I will not accept that.

What other IO tests can i run on this? I want a generic IO test, to see what the problem is.

 BTW, we also booted from an XP boot Disk, and the performance was the same on the server, so the OS can be ruled out.
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CHurst5841

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mysticaldan
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hi Dan,

All the drivers are ok, and bios is up-to date. I think you are correct about the data safeguard. I spoke with the HP rep, and he mentioned that since we oly have a 64mb cache on the server, we are getting no write cache, only read. He is going to lend us a 128mb upgade cache on monday to see the performance difference.

I will post back when i see the results.
Even with the 64 Mb cache it shud have 'write behind' enabled. Its a method of posting cache and improves performance dramtically. Even if u put in an additional 128 Mb of cache without write behind enabled the performance wont jump higher. With a RAID0 and a RAID5 on u cud do well with Write Behind enabled. Contact the HP dude for hw to go abt it or u must have had a utility that helps you do that. With Write Cache enabled even with 64 MB cache u'll see a marked difference in performance for sure.

Dan
With only the 64mb, the card can only use it for Read cache, when we add an additional 128, we can set a read/write ratio.
great. then once u have the read:write ratio set i am sure u'll find ur performance up by a signifactant ratio.

Dan
Yeah, the 128 mb additional increased performance by a factor of 20!!

For $400 CDN, I will take it anytime.

thanks for the assistance.

91mustang
And to think that people dont pay much attention to write behind caching ;-)

I am glad u have it sorted out now.

Cheers!!
Dan