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 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.
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"
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?