Re: Oracle Performance -- Possible Disk Bottleneck

On May 24, 5:56 pm, beth.sto..._at_gmail.com wrote:
> My apologies if this subject has been discussed. I searched the
> groups, and I couldn't find a good thread.
>
> We've been having performance problems with our Client/Server
> application for months. Users contantly complain of slow response
> times to their queries.
>
> Here's the environment:
>
> Oracle 9i on Windows. Poweredge 6850. 4, 3 GHz Quad Core
> Processors. 8 GB RAM. 9i databses are stored on an EMC Clarrion
> CX500 LUN -- RAID 10. 6, 15K 146GB dedicated disks. Oracle logs are
> stored on a separate RAID 10 LUN on dedicated disks. 1 GBE switched
> backend. Users connect using FastEthernet. XP clients. All disks on
> the SAN are fibre channel.
>
> CPU utilization is fine. RAM utilization is fine. Throughput on the
> NIC is fine -- maxes out at 50 Mbps for a short while when users first
> log in in the morning. Averages are 20 Mbps.
>
> Using perfmon in Windows, If I look at Disk Reads/Sec and Disk Writes/
> sec., here's what I see for averages:
>
> Disk Reads/sec = 2200 Avg
> Disk Writes/sec = 10 Avg
>
> Our reads/sec seem EXTREMELY high for only 80 users.
>
> Can someone help me understand if this is truly a disk bottleneck?
>
> Thanks in advance!

Don't use the windows tools to check on SAN performance. Talk with the storage admins. They will have a much better perspective on both throughput and utilization. The perfmon tool might indicate an issue, but I doubt it will tell much. I like the statspack suggestion if done accurately and snap are scoped correctly.

Do you have virus software running? This will typically bump up I/O reads in perfmon. Received on Fri May 25 2007 - 09:42:50 CDT