performance issue w/ Clariion cx500 and 11.11 system

[Mike Boswell_1]

We just migrated and oracle Db from a symmetrix to a cx500. The raid10 6 disk LUN is pegged at 100% when we have minimal activity. I am reading up on kernel parms and I see a kernel discrepancy between a functional system on the Clariion and the poor performance system. The following is on the poor perf system:

bufpages 12288 - (NPROC*3)
dbc_max_pct 50 - 50
nbuf 0 - 0

The system that performs well has:

bufpages 0 - (NBUF*3)
dbc_max_pct 10 - 10
nbuf 0 - 0

Also, Asyncdsk is out in the driver list and I understand this impacts disk performance.

I would appreciate any input from you all.

Thanks,

Mike

[Steven E. Protter]

Shalom,

Have the clone/cloning settings on the Clarion checked by EMC. Bad settings anywhere in the EMC can have massive impact on performance.

As far as dbc_max_pct goes, set it close to dbc_min_pct. Changing this value on the fly kills performance.

vx_ninode should not be set to zero, same issue as dbc_max/min_pct Generally set it to 90% of ninode.

A google search with site:itrc.hp.com will bring you lots of good performance links.

SEP