Red Hat said that its latest version of Red Hat Enterprise Linux (RHEL) 5.3 offers enhanced ability of the OS to run x86-64 virtualized environments. Red Hat increased to 126 the number of physical CPUs that can be supported per RHEL instance. It also boosted maximum memory per machine to 1TB. The company has also increased the limits on virtual CPU and memory, paravirtualized device drivers, and the number of allowed users for disks and network interfaces.

5.3 is the first version of RHEL that features a fully supported version of OpenJDK, an open-source implementation of Java SE 6. Red Hat said that any Java program written for Java SE 6 can now run RHEL 5.3.

Another new tool is a SystemTap. This is RHEL's first tracing and profiling application. RHEL 5.3 also has a new set of power-management controls and full-disk encryption at the block or file system level.

The new version of RHEL also aggregates the many bug fixes and comes with 150 software updates and upgrades. It supports Intel's Tylersburg/Nehalem.