Oracle checkpoint process suddenly using lots of CPU

Hi All,

Just a quick question! We've been running Oracle 8.0.5 on Solaris for some time without any major problems. Yesterday the Oracle Checkpoint daemon (ora_ckpt_<instance name>) seems to have changed its behaviour dramatically. Currently its using up to 90% of the CPU (per top) on our Enterprise 450. e.g.

  PID USERNAME THR PRI NICE SIZE RES STATE TIME CPU COMMAND

  372 oracle    14 -25    0   39M   20M run    22.4H 85.90% oracle
20251 robb       1  33    0 2168K 1392K cpu     2:22  0.20% top
  483 oracle    11  29    0   39M   24M sleep 163:27  0.17% oracle

Or, from ps -ef:
     UID   PID  PPID  C    STIME TTY      TIME CMD
  oracle   374     1  0   May 10 ?        0:04 ora_smon_RS2
  oracle   432     1  0   May 10 ?        0:18
/opt/oracle/product/8.0.5/bin/tnslsnr LISTENER -inherit
  oracle   362     1  0   May 10 ?        0:00 ora_pmon_RS2
  oracle   365     1  0   May 10 ?        7:36 ora_dbw0_RS2
  oracle   367     1  0   May 10 ?        0:50 ora_arch_RS2
  oracle   369     1  0   May 10 ?        7:04 ora_lgwr_RS2
  oracle   372     1 85   May 10 ?       1346:44 ora_ckpt_RS2
  oracle   376     1  0   May 10 ?        0:03 ora_reco_RS2
  oracle   483     1  0   May 10 ?       163:28 oracleRS2 (LOCAL=NO)

The Oracle server doesn't seem to be any busier than usual i.e. the client workload hasn't changed as far as I know. If I truss the process I don't see any obvious errors, mostly it seems to be calling pwrite() and some LWP related stuff. The alert log contains no unusual messages.

Any ideas why this would happen? Or better still, how to fix it?

--

Yours,
Robb.

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