Red Hat pushes out RHEL 6.4 beta
Looking ahead to Fedora 18 hardened as RHEL 7 in 2013
A day ahead of a set of announcements around optimizing IT operations that is scheduled for Wednesday, commercial Linux distributor Red Hat is rolling out the beta for its Enterprise Linux 6.X distro for servers and workstations.
The RHEL 6.4 beta previews what is coming in the next point release of the current branch of enterprise-grade Linux from Shadowman. The beta was announced by blog, which is how things in IT are done these days excepting the really big announcements where vendors try to get butts in seats.
The release notes for the RHEL 6.4 beta have more information, as you'd expect. Not that there is a huge amount of stuff in this beta, particularly with RHEL 7 expected to debut next year.
Here's a new feature that might give you a chuckle: the kernel in RHEL 6.4 has been tweaked so it can support up to 512 tape drives, more than four times that supported by the 6.3 kernel. Red Hat has also tucked in the Open vSwitch kernel module, which is an important feature for supporting software-defined networks based on OpenFlow. The kernel can now also gather up information on the "uncore" areas of Intel's Xeon 5500 and 5600 processors, with that term referring to L3 cache memory, memory controllers, and the interconnects that link the cores together.
On the virtualization front, the KVM hypervisor inside of RHEL 6.4 supports Opteron 4300 series processors as guests, including the new F16c, Trailing Bit Manipulation, BMI, and FMA instructions. (Advanced Micro Devices announced the Opteron 4300s as well as their Opteron 3300 baby siblings today.)
The QEMU guest agent underneath KVM has been updated to the upstream 1.1 version, which lets virtual memory and virtual disk be suspended on virtualized Windows guests as was already possible on Linux guests. The para-virtualized device drivers for RHEL for the Hyper-V hypervisor, which have already been rolled into the RHEL 5.9 beta in September, and now being embedded in RHEL 6.4 beta today. RHEL runs faster with para-virtualized drivers, and these Hyper-V drivers were recently adopted upstream by Linux kernel developers.
The para-virtualized drivers for RHEL for running atop VMware's ESXi hypervisor have also been added to the Anaconda installer so you don't go nuts looking for them if you happen to choose ESXi over KVM for your server virtualization layer.
As is usual with both dot releases and major releases, a slew of storage controller and network device drivers have been updated or added brand new with RHEL 6.4. The SystemTap tracing and probing tool is updated to version 1.8 in the beta, and the Parallel NFS (pNFS) client is still in tech preview; the latter includes support for Microsoft's Direct I/O, which allows for data to be read from disk to application buffers without stopping at file buffers.
RHEL 6.4 also has the ability to swap from main memory to remote disks over NFS, which is aimed at hosting providers and other hyperscale data center operators who run diskless server nodes.
The Red Hat Enterprise Linux release roadmap
As you can see from the roadmap above, RHEL 6.4 is expected sometime in early 2013, with a 6.5 update coming out in the late summer or early fall. (These dates are approximate in the above chart as well as being imprecise.)
RHEL 7 is expected to enter public beta in the first half of 2013, and will be a hardened version of the Fedora 18 development release that just went into beta last week and which, depending on the beta feedback, should be done by early January.
RHEL 7 should be the first commercial-grade Linux on ARM processors from Red Hat, and will also have full support for Linux container virtual private servers, which has been in tech preview on the latest RHEL 6.X releases. RHEL 7 will also have support for future "Ivy Bridge-EX" high-end Xeon E7 and "Haswell" Xeon family processors, and for 12Gb/sec SAS interfaces for storage.
Red Hat plans to support the ext4, XFS, or btrfs file systems for both boot and data, with ext4 and btrfs pushing up above 16TB of capacity and XFS hitting 500TB. These are tested limits, not the theoretical maximums. ®