Server NewsRed Hat Enterprise Linux 5.5 Released; RHEL 6 Coming Soon

Red Hat Enterprise Linux 5.5 Released; RHEL 6 Coming Soon

ServerWatch content and product recommendations are editorially independent. We may make money when you click on links to our partners. Learn More.

Red Hat is updating its flagship Linux server, Red Hat Enterprise Linux (RHEL), to version 5.5 providing performance and feature improvements.

This big release for the Linux server leader adds new capabilities — but when is Red Hat’s Enterprise Linux 6 coming out?

The new Red Hat (NYSE:RHT) release takes advantage of the latest Intel and AMD processors as well as advancements in virtualization and Windows interoperability. The release of RHEL 5.5 comes as Red Hat is about to begin to ramp up its next generation Red Hat Enterprise Linux 6 platform.

“We overlap on our releases as it takes many years to produce the new version – RHEL 6 – which is currently in development,” Tim Burke, vice president of platform engineering at Red Hat, told “Within the coming month we’ll have our beta release of Red Hat Enterprise Linux 6.”

Burke added that Red Hat will have some additional announcements on RHEL 6 likely coming out of their Red Hat Summit event in June. RHEL 6 will be the first major version update for Red Hat since the first release of RHEL 5 in 2007.

There is still lots of life left in the RHEL 5 platform though with a new point update to RHEL 5.5 now available. RHEL 5.5 has been in public beta testing since last month. The 5.5 update is the first update to RHEL in 2010; the RHEL 5.4 release came out in September of 2009.

One of the biggest new items in RHEL 5.5 according to Burke is hardware enablement for the latest Intel Westmere and AMD Opteron 6000platforms.

“The hardware is of nominal value until you’ve got the software to enable it and that’s what really shines in RHEL 5.5,” Burke said. “We’ve done a huge number of scalability enhancements for both bare metal and virtualization environments.”

In RHEL 5.5, Red Hat has improved workload processor scheduling to ensure that the required number of processor cores is being used. Burke added that Red Hat also focuses on I/O optimization in RHEL 5.5 which makes a difference for virtualization.

“In the past, a lot of workloads were not well suited for virtualization because the overhead incurred from an I/O operation could be as much as 30 percent,” Burke said. “But because of a lot of the new hardware capabilities that we’ve been able to optimize in RHEL 5.5, overhead for I/O bound workloads is now down to only 5 percent, so that opens up broad diversity of workload types that can on virtualization.”

Part of the I/O improvements come by way of support for Single Root I/O Virtualization (SR-IOV). Burke explained that SR-IOV provides KVM virtual machines with an improved ability to share hardware-bound PCI hardware resources.

New Run-Time Memory Allocation Feature

Virtualization also gets a boost by way of a new run-time memory allocation feature for RHEL 5.5’s KVM virtualization guests. Burke said that when an administrator has multiple virtual guests on the same system there is a need to make sure that no one guest can monopolize all of the physical memory. With the new feature, memory can be allocated based on need, policy and availability.

In RHEL 5.5, Red Hat has also improved interoperability with Microsoft’s Windows 7, though Burke was quick to note that the interoperability did not come by way of any deal with Microsoft. Rival Linux vendor Novell has a three year old agreement with Microsoft on interoperability and intellectual property related issues. The improved RHEL 5.5 interoperability involved the use of the open source Samba project which enables file and print services sharing between Windows and Linux.

“There is no special business deal related to Window interoperability,” Burke said. “It’s all work that we have pulled in with Samba and is done purely in the context of the upstream Samba development community of which Red Hat has several key contributors.”

Sean Michael Kerner is a senior editor at, the news service of, the network for technology professionals.

Follow ServerWatch on Twitter

Get the Free Newsletter!

Subscribe to Daily Tech Insider for top news, trends & analysis

Latest Posts

Related Stories