Oracle unveiled recently the release of the second functional update for Unbreakable Enterprise Kernel R6, positioned for use in the Oracle Linux distribution as an alternative to the standard package with the Red Hat Enterprise Linux kernel.
Unbreakable Enterprise Kernel 6 is based on Linux 5.4 (UEK R5 was based on 4.14 kernel), which has been enhanced with new features, optimizations, and fixesIt has also been tested for compatibility with most applications running on RHEL, and specially optimized to work with Oracle hardware and industrial software.
For those who do not know about this Kernel modified by Oracle, is positioned as an advanced set Linux kernel, positioned for use in the Oracle Linux distribution as an alternative to the normal Red Hat Enterprise Linux kernel package.
Unbreakable Enterprise Kernel (UEK) provides the latest open source innovations, key optimizations and security for cloud and on-premises workloads.
It is the Linux kernel that powers Oracle Cloud and Oracle Engineered Systems, such as Oracle Exadata Database Machine and Oracle Linux on Intel and AMD 64-bit or Arm 64-bit platforms.
UEK Release 6 maintains Red Hat Compatible Kernel compatibility (RHCK) and does not disable any features that are enabled in RHCK. Additional features are enabled to support key functional requirements and patches are applied to improve performance and optimize the kernel.
Unbreakable Enterprise Kernel R6U2 Main New Features
Unbreakable Enterprise Kernel Release 6 Update 2 is based on the Linux 5.4 Kernel and includes upstream LTS bug fixes, with additional patches to improve existing functionality and provide some minor bug fixes and security enhancements. Oracle continues to improve and apply critical bugs and security fixes to UEK R6. This update includes several new features, added functionality, and bug fixes on a variety of subsystems.
In this new version presented we can find that for cgroups, a new slab memory controller has been added which is notable for the transfer of slab accounting from the memory page level to the kernel object level, making it possible to share slab pages across different cgroups, rather than allocating separate slab caches for each cgroup.
The proposed approach allows to increase the efficiency of the use of slab, reduce the size of the memory used for the blocks By up to 50%, significantly reduce overall kernel memory consumption and reduce memory fragmentation.
Another change that stands out is related with Mellanox ConnectX-6 Dx devices, because it has been added a new vpda driver with support for vDPA framework (vHost Data Path Acceleration), which enables virtual machines to use VirtIO-based hardware acceleration for I / O.
It is also highlighted that an experimental possibility to limit the parallel execution of tasks is implemented in the task scheduler important on different CPU cores, to block leak channels associated with using a shared cache on the CPU.
Of the other changes that stand out of this new version:
- Ported improvements related to support for NVMe devices since Linux kernel 5.9.
- Moved fixes and enhancements for the Btrfs, CIFS, ext4, NFS, OCFS2, and XFS file systems.
- Updated drivers including lpfc 220.127.116.11 (Broadcom Emulex LightPulse Fiber Channel SCSI) 256 Gigabit mode for SCSI
- Fiber Channel, mpt3sas 36.100.00.00 (LSI MPT Fusion SAS 3.0), qla2xxx 0.02.00.103-k (QLogic Fiber Channel HBA).
- Added experimental support for VPN Wireguard, implemented at the kernel level.
- NFS adds experimental support for direct file copying between servers as defined in the NFS 4.2 specification
Finally, if you are interested in knowing more about this new released version, you can consult the details In the following link.
The kernel is available for x86_64 and ARM64 (aarch64) architectures. Kernel sources, including breakdown into individual patches, are posted to Oracle's Git public repository.