Oracle recently announced the release of its Unbreakable Enterprise Kernel (UEK) 8, a customized version of the Linux kernel that Oracle created and maintains for its own, designed to be faster, more secure, and more stable for businesses, especially those using Oracle products.
UEK is heavily optimized for enterprise workloads, such as databases and cloud applications. Oracle gives you full support for it if you’re using Oracle Linux, and it often includes newer features than those in the default Red Hat-style kernel.
Regarding the new version, Greg Marsden, Oracle’s senior vice president of Linux software development, described it as possibly the best release yet. So, let’s see what it brings to the table.
Among the standout enhancements in UEK 8 is the introduction of the folios data structure, which replaces the previous struct page to streamline memory management. This reduces overhead and significantly boosts scalability, critical for heavy enterprise workloads.
Additionally, the adoption of the Maple Tree data structure, which replaces traditional Red-Black Trees, delivers faster memory operations and efficient CPU cache utilization, resulting in quicker and smoother application performance.
Organizations utilizing Oracle Cloud Infrastructure with Arm-based Ampere processors will especially appreciate the flexibility offered by UEK 8. Users can now select between a standard 4K base page size kernel, ideal for constrained environments, and a newly configurable 64K page size kernel, better suited for high-performance computing workloads that demand extensive contiguous memory.
File system operations and I/O security have also seen considerable upgrades. Notably, io_uring, the kernel’s asynchronous I/O system interface, now boasts improved buffered writes for the XFS file system and optimizations that allow simultaneous direct I/O writes for both XFS and Ext4. Furthermore, Btrfs has gained enhanced performance capabilities, including efficient handling of larger data chunks and compressed data operations.
Another major highlight in UEK 8, especially for system administrators, is the inclusion of the XFS Online Repair feature, which is currently introduced as a technology preview. This groundbreaking functionality enables real-time validation and automatic repair of filesystem corruptions without downtime, drastically reducing system interruptions.
Networking capabilities have similarly advanced with the inclusion of BIG TCP, significantly improving IPv6 packet transmission efficiency and reducing latency in data centers. Additionally, Berkeley Packet Filter improvements include a dedicated memory allocator, enhancing the reliability and safety of kernel-level programming.
Lastly, on the security side, incorporating Intel Software Guard Extensions for Enclave Dynamic Memory Management equips UEK 8 with dynamic enclave resizing, bolstering protection for sensitive workloads in both cloud and on-premises environments.
For more information, see the announcement or check out the release notes.
Customers running Oracle Linux 9.5 can immediately benefit from UEK 8, available for installation from the “ol9_UEKR8” repository (which needs to be enabled first). Those on Oracle Linux 8 must first upgrade to Oracle Linux 9.
