The major themes of the release include pervasive virtualization, improved scalability and availability, increased power efficiency, and delivery of some of the latest software technologies. Now I will describe the highlights and noteworthy improvements in this RHEL 6 beta release.
- Comprehensive power management capabilities:
RedHat Enterprise Linux 6 is more focused on power consumption by improving the 'Time-keeping' within the kernel. It helps to transit the processors which don't have active tasks to idle state frequently. The result is cooler CPUs and greater power savings. The new monitoring tools like 'powertop' and tuning tools like 'tuned' are also worth mentioning.
- Performance enhancements
A great deal of kernel performance enhancement is implemented in RHEL 6 beta. RHEL 6’s process scheduler is completely rewritten so that higher higher-priority processes will run with minimal interferences from low-priority processes. Also there are substantial range of multi-processor lock synchronization enhancements like elimination of unnecessary locking occurrences, replacement of many spin locks with sleep locks and implementation of more efficient locking primitives.
- Scalability enhancements
Now a days high end servers with 64 CPUs and 2TB of memory in a 5U rack mount form factor are available. These systems and their successors are approaching the scalability limits of Red Hat Enterprise Linux 5. A primary feature of Red Hat Enterprise Linux 6 is that it is designed to provide the scalability to handle systems well into the future. Capabilities range from optimized support for large CPU counts and memory configurations to the ability to handle an increased number of system-interconnect buses and peripherals.
- Security features
Centralized management of identity and authentication is provided by a new service called System Security Services Daemon (SSSD). SELinux sandbox feature is also implemented in RedHat Enterprise Linux 6 beta.
- Resource management
With the RHEL 6 beta allows fine grained allocation management and control of hardware resources. It is made possible by addition of a new framework called Control Groups or cgroups. cgroups work at the process group level and can be used to manage resources ranging from CPU, memory, network and disk I/O for applications. This framework is also used to manage virtual guests.
Another important pint in this release is that RedHat has dropped Xen. However RHEL 6 is build with integrated KVM based virtualization.
- Storage & Filesystem
Fiber Channel over Ethernet ( FCoE ) and iSCSI protocol based network block storage devices are supported in RHEL 6. This release also includes ext4 and XFS filesystems. NFS has been updated to version 4, which includes support for IPv6.