Oracle releases Unbreakable Enterprise Kernel R5U2

Oracle Company released second functional update for the kernel Unbreakable Enterprise Kernel R5, positioned for use in the Oracle Linux distribution as an alternative to the regular package with the kernel from Red Hat Enterprise Linux. The kernel is available for x86_64 and ARM64 (aarch64) architectures. The source code for the kernel, including the breakdown into individual patches, published in the public Oracle Git repository.

Unbreakable Enterprise Kernel 5 is based on the kernel Linux 4.14 (UEK R4 was based on the 4.1 kernel), which is updated with new features, optimizations, and fixes, as well as being tested for compatibility with most applications running on RHEL, and specifically optimized to work with industrial software and Oracle hardware. Installation and src packages with UEK R5U1 kernel prepared by for Oracle Linux 7.5 and 7.6 (there are no restrictions on using this kernel in similar versions of RHEL, CentOS and Scientific Linux).

Key improvements:

• Ported patches with the implementation of the PSI (Pressure Stall Information) subsystem, which allows you to analyze information about the waiting time for obtaining various resources (CPU, memory, I / O) for certain tasks or sets of processes in a cgroup. With PSI, user-space handlers can more accurately assess system load and slowdown patterns compared to Load Average;
• For cgroup2, the cpuset resource controller is enabled, which provides a mechanism for limiting the allocation of tasks by NUMA memory and CPU nodes, allowing the use of only resources defined for a group of tasks through the cpuset pseudo-FS interface;
• The ktask framework has been implemented to parallelize tasks in the kernel that consume significant CPU resources. For example, with the help of ktask, parallelization of operations for clearing memory page ranges or processing the list of inodes can be organized;
• In DTrace added support for capturing packets via libpcap with the new action "pcap(skb,proto)" For example "dtrace -n 'ip:::send { pcap((void *)arg0, PCAP_IP); }'";
• From new kernel releases carried over fixes in the implementation of FS btrfs, CIFS, ext4, OCFS2 and XFS;
• From kernel 4.19 carried over changes related to support for KVM, Xen and Hyper-V hypervisors;
• Updated device drivers and expanded support for NVMe drives (transferred changes from kernels 4.18 to 4.21);
• Applied settings to optimize performance on ARM platforms.

Source: opennet.ru