The heap usage is 92%.

Target type=Oracle WebLogic Server
Target name=XXXXX
Categories=Capacity
Message=The heap usage is 92%.
Severity=Critical
Event reported time=May 6, 2014 5:01:22 AM
Operating System=Linux
Platform=x86_64


Solution:
======

We have been receiving the below alert for heap usage for OMS frequently, we Increased the max heap memory setting.

Here are the couple of steps to be  performed in attaining this.

1. $emctl stop oms -all

2.  For Unix platforms:

Please have a backup and edit the file /gc_inst/user_projects/domains/GCDomain/bin/setDomainEnv.sh as follows:

Change the following line from

  CUSTOM_MEM_ARGS_64BIT="-Xms${XMS_SUN_64BIT}m -Xmx${XMX_SUN_64BIT}m"
to
 CUSTOM_MEM_ARGS_64BIT="-Xms512m -Xmx1024m"

3. Start the OMS
OMS_HOME/bin/emctl start oms

FYI: EM 12c: Heap Usage Metric Generating Critical Alerts for EMGC_ADMINSERVER target (Doc ID 1482205.1)

Log Files in RAC Environment

Log Files in RAC Environment:

The Cluster Ready Services Daemon (crsd) Log Files

Log files for the CRSD process (crsd) can be found in the following directories:

ORA_CRS_HOME/log/hostname/crsd

the crsd.log file is archived every 10MB as crsd.101, crsd.102 ...
ORACLE_CRS_HOME/log//alert.log

Oracle Cluster Registry (OCR) Log Files

The Oracle Cluster Registry (OCR) records log information in the following location:

ORA_CRS_HOME/log/hostname/client

Cluster Synchronization Services (CSS) Log Files

You can find CSS information that the OCSSD generates in log files in the following locations:

ORA_CRS_HOME/log/hostname/cssd
OCSSD responsible for inter node health monitoring and instance endpoint recovery.

It runs as oracle user.  

The cssd.log file is archived every 20MB as cssd.101, cssd.102....

Event Manager (EVM) Log Files

Event Manager (EVM) information generated by evmd is recorded in log files in the following locations:

ORA_CRS_HOME/log/hostname/evmd

RACG Log Files

The Oracle RAC high availability trace files are located in the following two locations:

ORA_CRS_HOME/log/hostname/racg
$ORACLE_HOME/log/hostname/racg

Core files are in the sub-directories of the log directories. Each RACG executable has a sub-directory assigned exclusively for that executable. The name of the RACG executable sub-directory is the same as the name of the executable.

VIP Log Files

You can find VIP related log files under following location :
ORA_CRS_HOME/log/nodename/racg

OCR logs
OCR logs (ocrdump, ocrconfig, ocrcheck) log files are stored in $ORA_CRS_HOME/log//client/ directory.

SRVCTL logs
srvctl logs are stored in two locations, $ORA_CRS_HOME/log//client/ and in $ORACLE_HOME/log//client/ directories.