The RHEL 5.5 update provides a number of virtualization enhancements, and the support for new servers with large memory systems allows a larger number of virtual machines to be deployed on each physical server. Huge page support is now automatic and extended to virtual guests, improving the performance of memory-intensive applications. Support for Single Root I/O Virtualization (SR-IOV) offers virtual guests an improved ability to share PCI hardware resources and more efficient access I/O devices, and according to Red Hat, further I/O optimizations can help improve flexibility when migrating virtual guests across physical systems.

Tim Burke, vice president of platform engineering at Red Hat, shared some of the update specifics with The Register. Burke said that in RHEL 5.5 the operating system is more aware of the system topology and instruction streams and data are now physically close because of the memory allocation and job scheduling changes. More work is also placed on as few cores as possible due to kernel changes, which allows servers to conserve power.

RHEL 6 availability will be announced in June, and a beta of RHEL 6 should be available later in April according to a statement by Burke.