memory problem - oracle 10203 on HPUX

folks,

I have a machine (RAC configuration) 10.2.0.4 on HPUX - PARISC. in a node I have 38GB physical memory, 8 processors. the machine could not run with asynchronous IO, so I set io slave to 8, and dbwr to 1.

at AWR report, it said that 2GB memory for PGA is enough, and 12GB of SGA mostly enough.
concurrent user is 1000 until maximum 1500 users connected. at one time only 30-50 concurrent active with OLTP transaction.

at the OS perspective, it said that mostly 90-100% memory has been used, even when high load, 50% of the swap will be used also. almost every 20 days, the server is rebooted itself, I think this is due to lack of memory....

why between OS and oracle side there has much big different of memory usage???

-- 
regards
ujang

"I believe that exchange rate volatility is a major threat to
prosperity in the world today"
Dr. Robert A. Mundell, Nobel Laureate 1999
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