Help! Slow Performance

[Henry Nguyen]

Hi,

I'm running Oracle 9i on HP-Ux 11.0. The database is spread out across /u01 to /u09. I've looked at memory and disk IO contention, and they don't seem to be the culprit. However, when I looked at fragment size, it is set differently for each filesystem. Please see attached from df -g. Could this the culprit behind the performance problem? Oracle block size is set at 16k.

Thanks for all your help.
Henry

[twang]

It is not recommended to have the Oracle block size smaller than the OS one.
if your database is OLTP then 16K is way too large more than likely. I would try some test with 4k and 8k block sizes. I have had a case where 4k was perfect and 8k actually slowed performance.

[Saurav_1]

Hi,

Fine tuning the system on guess work may degrade the system performance. I recommend and hope that you have glance and MWA installed on this system for performance checking. Now to check the overall past performance of the system. Download HP openview Performance manager for windows NT. and install on a PC in network. use tutorial, even product is easy to use. Its version is free for initial 2 months. Take care of following Points.
1) Give the full harware description of server
2) Check the usage of SWAP space using sar and glance
3) Free memory usage & availability.
4) Enabled Virtual Swap even slows the performance of system with High Physical Memory installed. Check thru sam.
5) HP-UX 11 version comes with POPS(Performance optimised Page Size) try to use this feature to improve the performance.
6) Filesystem cache is enabled on the system by default, and oracle uses its own caching scheme of latest accessed data. BOTH the cacheing can degrade the system. Try if U can disable the FS caching on ur oracle Filesystem.
7)Try to fine tune the kernel according to requirement. caching features can be managed from tuned parametres.

[Suresh Patoria]

Hi,

Pls check the disk utilisation using the sar -d 1 4 command

i want to know that u using the any storage

if it is then pls mention

thanx

[Henry Nguyen]

Hi Suresh,

I'm not using any storage, it's only JBOD. I've attached an output of the disk utilization as you have requested.

Thanks,
Henry