| Oracle FAQ | Your Portal to the Oracle Knowledge Grid | |
 |
 | |||
| Oracle FAQ | Your Portal to the Oracle Knowledge Grid | |
|
| |||
Home -> Community -> Mailing Lists -> Oracle-L -> Important: Oracle processes taking lots of CPU
Hi all,
Please forgive my ignorance if the details provided by me are not sufficient, or I'm not doing proper analysis.
11.5.8 on 9.2.0.5 O/s HP-UX Risc 64 B.11.11
We are facing a unique problem. Lots of DB processes take close to 100% CPU and an overall CPU time of more than 500 mins. This happens with lots of different applications/forms. The problem doesn't happen all the time i.e. if the same form is run 10 times, only 1-2 faces that kind of problem.
With my limited knowledge I've been able to get the following details about the problem.
The DB processes take a huge amount of CPU time. This fact is not reflected in v$sesstat or the 10046 trace files. There are processes which take more than 500 mins. of CPU time, but the trace file doesn't account for even a tiny fraction of that.
When monitoring the process at the OS, the process takes close to 100% CPU all the time, but the CPU stats in v$sesstat doesn't increase.
I did a truss on the processes consuming 100% CPU and it shows the following line repeating infinitely:
select(2048, 0x800003fffdffb3d0, 0x800003fffdffb4d0, 0x800003fffdffb5d0, 0x800003fffdffb6d0) = 0
v$session_wait shows some wait event like "latch free", "db file sequential read" but with STATE = waited known time, but the seconds_in_wait keeps increasing while the process keeps taking 100% CPU all the while.
Please let me know if anyone has faced a similar issue. How do I find out what is the process doing which is eating up all the CPU?
I think that the problem is somehow at the O/S level, since trace files don't indicate anything wrong, same forms when run again, run without taking much CPU.
Regards
New DBA
-- http://www.freelists.org/webpage/oracle-lReceived on Tue Nov 23 2004 - 04:54:25 CST
 |
 |