WARNING: Heavy swapping observed on system in last 5 mins

Applies to:

Goal

The document explains why you may see the following WARNING in the alert log after upgrading to 11.2.0.3.

Fix

The reason you may now see these informational messages in the alert is due to the fact that in 11.2.0.3 an enhancement fix was included for unpublished
Bug 10220118 - Print warning to alert log when system is swapping (Doc ID 10220118.8)

Please refer to
Note 10220118.8 - Bug 10220118 - Print warning to alert log when system is swapping



Description

  This fix is really an enhancement.
  With this fix a warning is printed to the alert log (and DBRM trace)
  if excessive swapping is observed on the system.
  The warning will not be printed more than once per hour.
  

The same issues could have been happening on 11.2.0.2 but they simply would not have been reported.
There is no cause for concern and we suggest that the databases are just monitored as usual.

If you look in the alert log, you will see that the message does not happen every hour. 
If SWAP was causing any serious issue we could also see ORA-4031/ORA-4030 and would then be able to use the DBRM trace in conjunction with obtaining further diagnostics.

- If your Platform. is IBM-AIX then This is not the only reason for this alert log file. There is a known port-specific bug for IBM AIX on POWER Systems (64-bit):

Bug 14731911 : FALSE SWAP WARNING MESSAGES PRINTED TO ALERT.LOG ON AIX
Base Bug 11801934 : WRONG PAGE-IN AND PAGE-OUT OS VM STATS IN AIX.

Solution for AIX

Apply patch 11801934 if available for your platform. or request a patch to Oracle Support in a new Service Request.