Oracle Database Discussions

I am try to find a performance problem in a new 11gR2 database running on Linux x86-64 on a virtual server.

I noticed in the ASH report, section "Top Background Event", we see that "CPU + Wait for CPU" represents 63.98% of the activity during the analysis period.

We can also see that in "TOP Sessions" that 63.22% of the event "CPU + Wait for CPU" is generated by the PSP0 process (Process spawner).

What could be the cause of the high activity generated by the PSP0 process.

Content of the alert.log for the analysis period:

1 mai 2012 18:31:21 EDT UNKNOWN 16


Incremental checkpoint up to RBA [0xa4d.8d2d.0], current log tail at RBA
[0xa4d.8dde.0]
1 mai 2012 18:01:14 EDT UNKNOWN 16


Incremental checkpoint up to RBA [0xa4d.80e7.0], current log tail at RBA
[0xa4d.8b83.0]
1 mai 2012 17:31:07 EDT UNKNOWN 16


Incremental checkpoint up to RBA [0xa4d.7f47.0], current log tail at RBA
[0xa4d.7ff9.0]
1 mai 2012 17:00:58 EDT UNKNOWN 16


Incremental checkpoint up to RBA [0xa4d.6928.0], current log tail at RBA
[0xa4d.7406.0]
1 mai 2012 16:44:58 EDT UNKNOWN 16


Completed checkpoint up to RBA [0xa4d.2.10], SCN: 42156409
1 mai 2012 16:39:56 EDT UNKNOWN 16


Archived Log entry 633 added for thread 1 sequence 2636 ID 0x596fa004
dest 1:
1 mai 2012 16:39:54 EDT UNKNOWN 16


Current log# 3 seq# 2637 mem# 1: /oracle/SS4/mirrlogA/log_g13m2.dbf
1 mai 2012 16:39:54 EDT UNKNOWN 16


Beginning log switch checkpoint up to RBA [0xa4d.2.10], SCN: 42156409
1 mai 2012 16:39:54 EDT UNKNOWN 16


Thread 1 advanced to log sequence 2637 (LGWR switch)
1 mai 2012 16:39:54 EDT UNKNOWN 16


Current log# 3 seq# 2637 mem# 0: /oracle/SS4/origlogA/log_g13m1.dbf
1 mai 2012 16:30:50 EDT UNKNOWN 16


Incremental checkpoint up to RBA [0xa4c.34fdf.0], current log tail at
RBA [0xa4c.35146.0]
1 mai 2012 16:00:43 EDT UNKNOWN 16


Incremental checkpoint up to RBA [0xa4c.314fe.0], current log tail at
RBA [0xa4c.32839.0]