After APM agent instrumentation, WebLogic instance under Red Hat Linux shows this non-fatal message at startup: "Java HotSpot(TM) 64-Bit Server VM warning: Failed to reserve shared memory (errno = 22)"

Article Id: 8220

Status: Published

Updated On: 14-02-2018 07:56

Legacy Id: TEC1305196

Products:

CA Application Performance Management Agent (APM / Wily / Introscope) , INTROSCOPE

Issue/Introduction:

After APM agent instrumentation, WebLogic instance under Red Hat Linux shows this non-fatal message at startup:

Java HotSpot(TM) 64-Bit Server VM warning: Failed to reserve shared memory (errno = 22)

Cause:

Cause is unrelated to APM Agent. The option "-XX:+UseLargePages" had been included the JVM arguments which requires explicit hugepages (libhugetlbfs) to be setup on the Red Hat Linux OS.

Environment:

APM 9.x, 10.x Java AgentWebLogic Server under Red hat Linux

Resolution:

EITHER:

Ensure that the explicit hugepages (libhugetlbfs) setup on the Red Hat Linux OS is complete and accessible for the userid running the WebLogic instance.

OR:

Remove the argument "-XX:+UseLargePages"

Additional Information:

For further information including advantages/disadvantages of the Java large pages options see: Oracle Java 8 documentation

Red hat Customer Portal: How do I enable large page support on Linux?