This is due to the Operating System's GLIBC libraries.
ExplanationThe high virtual memory allocation is due to RHEL 6's GLIBC libraries. There is an OS setting that can further tune the virtual memory allocation if needed. The instructions are found in the following links:
- Why do some applications use significantly more virtual memory on RHEL 6 compared to RHEL 5
- Linux RHEL6 allocates more memory to run java program
- Linux glibc >= 2.10 (RHEL 6) malloc may show excessive virtual memory usage
Tests were run in-house to demonstrate this scenario. Two Netprobes running the same set of JMX samplers were installed on RHEL 5 and 6 machine. Below are the results:
RHEL 5 Netprobe (~1GB virtual memory)
RHEL 6 (~8GB virtual memory)