Red Hat Enterprise Linux, now a staple in data centers of all shapes and sizes, enters its 9th year of availability this month with the announcement of version 6. The release is more than three years in the making.

Nick Carr, Red Hat's marketing director, told NetworkWorld that RHEL6 is "setting the scene for the rest of the decade." Enterprise Linux is supported for seven years after release, so this will be the dominant version for the next 10 years. Support for RHEL5 ends in March 2014.

"From a technology viewpoint, we want customers and applications to have the same experience whether they're deploying in a physical, virtual, or cloud environment," said Carr. Although cloud technologies are not integrated directly in RHEL6 today, Red Hat's positioning of RHEL6 and emerging technology support of the Deltacloud API project leave little question that the company is betting big on cloud technology. A slew of new features are aimed at improving consolidation and reducing the computing footprint. Red Hat focused on scalability for SMP systems with large CPU counts, reduced power consumption through kernel time-keeping improvements, better resource control, and reduced environmental impact. In addition, changes to the storage subsystem now allow online resizing of multipath volumes with LVM. Improvements have also been made to memory handling with KVM. A new feature called kernel shared memory (KSM) allows the kernel to identify and share identical pages among guests. When several guests of the same type and nature are running, this feature drops memory requirements, increasing consolidation ratios. In RHEL5, Red Hat introduced support for the Xen hypervisor. However, the company moved to KVM with RHEL5 release 4. RHEL version 6 will support only KVM, and a conversion tool will be available to help customers migrate from Xen guests. When asked about changes to the current subscription model, Carr said that no final decisions have been made. "It's probable that there will be some changes to the subscription simply based on the demand and breadth of market that the product moves in."