Oracle Linux (Oracle Enterprise Linux)

Main Article: Operating Systems

The Unbreakable Enterprise Kernel is part of the Oracle Linux operating system, formerly known as Oracle Enterprise Linux. Created by the joint efforts of Oracle development teams in the areas of Linux, databases, binding software and hardware, the Unbreakable Enterprise Kernel Linux kernel has the following characteristics:

• Speed: performance increase over 75% compared Red Hat to the Compatible Kernel version in OLTP tests; 200% faster InfiniBand messaging increase the speed of access to solid-state drives () SSD by 137%.
• Modernity: Provides optimization for large NUMA servers (distributed shared memory architecture) Improved power management and energy efficiency more accurate control of processor and RAM resources.
• Reliability: support for Data Integrity Extensions information protection and the T10 Protection Information Model to prevent corrupted data from being written to the storage device; Hardware failure protection to improve application uptime Low traceability performance.
• Optimization for Oracle Products: Designed and tested for the best performance and highest reliability-with Oracle hardware, databases, and bundling software.
• The new version of the Oracle Exadata Database Machine and the new Oracle Exalogic Elastic Cloud binding software machine use the Unbreakable Enterprise Kernel to achieve an unprecedented level of Linux performance.

The Unbreakable Enterprise Kernel is based on the main current version of the Linux kernel 2.6.32 and will continue to evolve so that customers can quickly take advantage of both Oracle innovations and developer community improvements.

2022

Oracle Linux 8.7

Oracle has published the release of the Oracle Linux 8.7 distribution, based on the Red Hat Enterprise Linux 8.7 package base. This became known on November 21, 2022. For download without restrictions, 11 GB and 859 MB iso installation images prepared for x86_64 and ARM64 architectures (aarch64) are distributed. Oracle Linux has unlimited and free access to the yum repository with binary updates to errata packages and security issues. Separately supported Application Stream modules have also been prepared for download.

In addition to the RHEL kernel package (based on the 4.18 kernel), Oracle Linux offers its own Unbreakable Enterprise Kernel 7 kernel, based on the Linux 5.15 kernel and optimized for working with Oracle industrial software and equipment. Kernel sources, including breakdown into individual patches, are available in Oracle's public Git repository. The Unbreakable Enterprise Kernel is installed by default, positioned as an alternative to the standard RHEL kernel package, and provides a number of advanced features such as DTrace integration and improved Btrfs support.

In addition to the delivery of the Unbreakable Enterprise Kernel R7 kernel, the functionality of the Oracle Linux 8.7 and RHEL 8.7 releases is completely identical (the list of changes in Oracle Linux 8.7 repeats the list of changes in RHEL 8.7)^[1].

Oracle Linux 9 Release and Unbreakable Enterprise Kernel 7 (UEK R7)

On July 6, 2022, it became known that Oracle published stable releases of the Oracle Linux 9 distribution and the Unbreakable Enterprise Kernel 7 (UEK R7) kernel, positioned for use in the Oracle Linux distribution as an alternative to the standard kernel package from Red Hat Enterprise Linux. The Oracle Linux 9 distribution is based on the Red Hat Enterprise Linux 9 package base and is fully binary compatible with it.

Oracle Linux 9

As explained, for download without restrictions, installation iso-images are offered, measuring 8.6 GB and 840 MB, prepared for x86_64 and ARM64 architectures (aarch64). Oracle Linux 9 has unlimited and free access to the yum repository with binary updates of errata and security issues. Separately supported repositories with Application Stream and CodeReady Builder package sets have also been prepared for download.

In addition to the package with the kernel from the composition RHEL (based on the 5.14 kernel), Oracle Linux offers its own Unbreakable Enterprise Kernel 7 kernel, based on Linux the 5.15 kernel and optimized for working with Oracle industrial software and equipment. Kernel sources, including breakdown into individual patches, are available in Oracle's public Git repository. The Unbreakable Enterprise Kernel is installed by default, positioned as an alternative to the standard RHEL kernel package, and provides a number of advanced features such as DTrace integration and optimized Btrfs support. In addition to the additional kernel for functionality, the releases of Oracle Linux 9 and RHEL 9 are completely identical (a list of changes can be viewed in the RHEL9 announcement).

Key changes to the Unbreakable Enterprise Kernel 7 core:

• Optimized support for Aarch64 architecture. The default memory page size on 64-bit ARM systems is reduced from 64 KB to 4 KB, which is better combined with the memory and load types typical of ARM systems.
• The delivery of the dynamic debugging system DTrace 2.0, which was transferred to the use of the eBPF kernel subsystem, has continued. DTrace 2.0 works on top of eBPF, similar to how existing trace tools in Linux work on top of eBPF.
• The capabilities of the Btrfs FS have been expanded. Btrfs has added an asynchronous implementation of the DISCARD operation to mark freed blocks that can no longer be physically stored. Asynchronous implementation allows you not to wait for the disk to complete DISCARD and perform this operation in the background. Mount options have been added to optimize the recovery of data with corrupted FS: "rescue = ignorebadroots" for mounting, despite damage to some root trees (extent, uuid, data reloc, device, csum, free space), "rescue = ignoredatacsums" for disabling checksum verification for data, and "rescue = all" for simultaneously turning on the 'ignorebadroots', 'ignoredatacsums' and 'nologs' modes. Significant performance optimizations related to fsync () operations have been made. Added support for fs-verity (authentication and file integrity) and user ID mapping.
• XFS supports DAX operations for direct access to the FS, bypassing the paged cache to eliminate double caching. Changes have been added to solve problems with the overflow of the 32-bit time_t data type in 2038, including the bigtime and inobtcount mount options.
• Changes have been made to the OCFS2 File System (Oracle Cluster File System).
• Added ZoneFS file system, optimizing low-level work with zoned storage devices. Zoned drives mean devices on hard magnetic drives or NVMe SSDs, the storage space in which is divided into zones that make up groups of blocks or sectors, to which only sequential addition of data is allowed with updating the entire group of blocks. ZoneFS connects each zone in the drive to a separate file that can be used to store data in raw mode without manipulation at the sector and block level, i.e. allows applications to use the file API instead of directly accessing the block device using ioctl.
• Stabilized support for VPN WireGuard protocol.
• Enhanced eBPF capabilities. The CO-RE (Compile Once - Run Everywhere) mechanism is implemented, which solves the problem with the portability of compiled eBPF programs and allows you to collect the code of eBPF programs only once and use a special universal loader that adapts the downloadable program to the current kernel and BTF types (BPF Type Format). The BPF trampoline mechanism has been added, which allows you to practically reduce the overhead when transferring calls between the kernel and BPF programs to zero. Provided the ability to directly access kernel functionality from BPF programs and suspend the handler.
• Integrated detector of split locks that occur when accessing unaligned data in memory due to the fact that when executing an atomic instruction, the data crosses two lines of the CPU cache. The kernel can detect such locks on the fly, which lead to a significant drop in performance, and issue warnings or send a SIGBUS signal to the application that caused the lock.
• Support is provided for Multipath TCP (MPTCP), an extension of the TCP protocol to organize the operation of a TCP connection with the delivery of packets simultaneously over several routes through different network interfaces associated with different IP addresses.
• The task scheduler implements a SCHED_CORE planning mode that allows you to control which processes can be jointly executed on one CPU core. Each process can be assigned a cookie identifier that defines the area of trust between processes (for example, belonging to one user or container). When organizing code execution, the scheduler can only share a single CPU core for processes associated with a single owner, which can be used to block some Spectre class attacks by preventing worthy and untrustworthy tasks from running in a single SMT (Hyper Threading) thread.
• For cgroups, a slab memory controller is implemented, which is notable for transferring slab accounting from the level of memory pages to the level of kernel objects, which makes it possible to share slab pages in different cgroup instead of allocating separate slab caches for each cgroup. The proposed approach allows you to otimize the efficiency of using slab, reduce the size of memory used for slab by 30-45%, reduce the total memory consumption by the kernel and reduce memory fragmentation.
• The supply of debug data in CTF (Compact Type Format) format is provided, which provides compact storage of information about C-types, relationships between functions and debug symbols.
• The DRBD (Distributed Replicated Block Device) module and the/dev/raw device have been discontinued (use the O_DIRECT flag for direct file access^[2]

2015

Oracle Linux is available in the Docker Hub Registry repository

On February 9, 2015, Oracle announced the availability of Oracle Linux images in the Docker Hub Registry, a repository of Docker-based components, including applications and operating systems (OS).

In addition to Oracle Linux, Docker Hub is included, DBMS MySQL which is hugely popular and downloaded millions of times. At the end of February, the corporation Oracle plans to provide a supported Oracle image MySQL for official Docker Hub repositories so that developers can quickly take advantage of the latest innovations in MySQL.

The availability of Oracle Linux and MySQL in the Docker Hub Registry will provide Docker users with the ability to build applications, effectively using a more rational container-based approach for distributed application deployment, with the confidence of enterprise-class products. In addition, developers can use Docker tools without the need to separately download OS images and manually import them into their own repository, which saves time and simplifies work with the tools.

The enterprise-class Linux distribution with commercial support includes the following features:

• Oracle Ksplice technology - allows the system administrator to apply updates to the core OS in working mode without interrupting the execution of applications in Docker containers. In addition, the ability to apply patch packages to protect the kernel without allocating maintenance time provides increased security and availability.

• Support for different versions and Oracle Unbreakable Enterprise Kernel - Oracle Linux images in Docker are available for Oracle Linux 6 and 7 and use the new Unbreakable Enterprise Kernel. The Oracle and supported container environment gives developers and system administrators maximum flexibility to run Oracle Linux 6 or Oracle Linux 7 containers on any version of the OS.

• Free use, distribution and upgrade - Docker images for Oracle Linux are available on the same model as Oracle Linux - just download and use. Existing Oracle Linux clients receive support for Docker under existing support agreements.

• Flexibility with Oracle Unbreakable Enterprise Kernel - Because the new Unbreakable Enterprise Kernel runs on Oracle Linux 6 and Oracle Linux 7, users can choose which version of the OS to use, potentially eliminating the need to upgrade applications and improving compatibility with other components.

Oracle Linux 6.7 Industrial Distribution Released

July 30, 2015 Oracle introduced the release of the industrial distribution Oracle^[3].

It is based on the Red Hat Enterprise Linux 6.7 package base. The distribution is available for free download in assemblies for the x86_64 architecture. Oracle Linux users have unlimited and free access to the yum repository with binary updates to errata and security issues.

Oracle Linux 6.7 includes three versions of packages with a Linux kernel:

• classic from Red Hat (kernel-2.6.32-573.el6 for x86 and x86_64),
• Unbreakable Enterprise Kernel Release 2 (kernel-uek-2.6.39-400.250.7.el6uek)
• Unbreakable Enterprise Kernel Release 3 (kernel-uek-3.8.13-68.3.4.el6uek для x86_64).

The basic distribution package for the i386 architecture includes a core from RHEL and Unbreakable Enterprise Kernel Release 2, and for the x86_64 architecture - a core from RHEL and Unbreakable Enterprise Kernel Release 3.

Unbreakable Enterprise Kernel 3 is based on the Linux 3.8 kernel and integrates DTrace support, LXC isolated container system, improved Btrfs support and significantly expanded hardware support. Ready-made binary kernel builds from Oracle for RHEL-compatible distributions and src.rpm packages are presented on the site public-yum.oracle.com. Oracle does not impose any restrictions on the supply of the kernel prepared in Oracle in third-party products.

Among the features of this version:

• enabling OpenSCAP (Open Security Content Automation Protocol) support for automated system security monitoring,
• providing official support for Keepalized and HAProxy for load balancing and fault tolerant configurations,
• SSSD support extension for Active Directory,
• hyper-daemons package update (hypervfcopyd, hypervkvpd, hypervvssd).

Unbreakable Enterprise Kernel 3 update released

On August 1, 2015, Oracle announced the release of the sixth functional update for the Unbreakable Enterprise Kernel 3 (UEKR3U6) kernel. Source code, including patch breakdown, is available in the Oracle Git repository ^[4] the ^[4].

The kernel is positioned as an alternative to the standard kernel package supplied with Red Hat Enterprise Linux and provides a number of advanced features:

• DTrace integration
• improved Btrfs support.

Kernel packages are prepared for Oracle Linux 6 and Oracle Linux 7.

The most notable changes are:

• Support for installation and use on systems with UEFI Secure Boot;
• Kernel modules are now digitally signed using the SHA-512 algorithm (SHA-256 was previously used).
• Included is the sb_edac driver for Intel Sandy Bridge processor memory controllers;
• Support for the SGI UltraViolet 3 platform has been implemented;
• The LXC Container Management Toolkit has been updated. Added the ability to specify the "--privilege" option when creating containers;
• Made improvements to the Xen hypervisor, solved problems with "freezes" and memory leakage in the block device driver;
• DTrace adds the ability to use user-defined checks for 32-bit applications running on 64-bit hosts;
• More than 8 hardware PTP hours are supported;
• Update drivers for storage and network cards Adaptec, Broadcom, Cisco, Emulex, Intel, QLogic, VMware;
• The Open Vswitch module (kmod-openvswitch-uek) has added support for VXLAN (Virtual eXtensible Local Area Network) and GRE (Generic Routing Encapsulation);
• Added snic driver for Cisco SCSI NIC;
• Fixed bugs in btrfs, ext4, xfs and OCFS2 file systems.

Oracle released Linux 7.2

November 26, 2015 Oracle introduced the release of the industrial distribution Linux 7.2, created on the basis of the package base Red Hat Enterprise Linux 7.2^[5].

For download without restrictions, but after free registration, an installation iso-image is distributed, measuring 4.7 GB, prepared for the x86_64 architecture. Oracle Linux also has unlimited and free access to the yum repository with binary updates to errata and security issues.

The composition included two versions of the Linux kernel: the original kernel from RHEL 7.2 (a branch from the original kernel 3.10) and the package developed by Oracle with the Unbreakable Enterprise Kernel Release 3 Update 7 (a branch from the kernel 3.8). In addition to the kernel, Oracle Linux 7.2 is similar in functionality to RHEL 7.2.

Features of Oracle Linux 7.2 include:

• the makedumpfile utility has been switched to using the sadump format to create kernel dumps if the system has more than 16 TB of RAM;
• the text installer has added the ability to configure kdump at the stage of system installation;
• added the ability to install MySQL 5.6 Community Edition from the Anaconda installer or when using kickstart mode;
• OpenSCAP updated to release 1.2.5;
• Technology Preview continues to test support for the Ceph distributed file system, the Deo disk encryption system, the DRBD distributed replicated block device, the OpenSCAP installer add-on, the tmem (Transcendent memory) subsystem, and UEFI Secure Boot.

2014

Oracle Linux 7

July 31, 2014 Oracle Corporation about the availability for download of the distribution kit of the new version of Oracle Linux 7 OS.

The corporation has identified this release as being distributed free of charge, the only major enterprise-class Linux distribution. It publishes all bug fixes, both code and security-related bugs, providing more flexibility and choices than any other commercial Linux distribution.

The new version of Oracle Linux relies on Oracle's approach, which provides support for new, promising technologies like OpenStack, combined with providing customers and partners with the advanced Linux innovations, tools, and features needed to build enterprise-class solutions for today's data center.

Oracle Linux 7 features include XFS and Btrfs file systems, Linux Containers (LXC) container utilities, DTrace dynamic tracing system, Ksplice technology (Linux kernel extension), Xen hypervisor enhancements, and Unbreakable Enterprise Kernel Release 3.

The Oracle Linux 7 distribution can be downloaded from the Oracle Software Delivery Cloud website. All code bug fixes and security bugs are published on Oracle Public Yum Servers, allowing organizations to install the same software revision on all system deployments, with or without subscription to technical support services, and create a simple migration path, from free to commercial. No reinstallations are required.

2013

Oracle Linux 6.5

On December 13, 2013, Oracle announced the release of Oracle Linux 6.5.

The updated distribution kit includes the default innovative Unbreakable Enterprise Kernel Release 3 kernel (based on Linux 3.8) to provide instant access to new Linux features and improvements.

Oracle Linux 6.5 has new security features, including a common cryptographic data store for applications that encryption tools can use to process trusted certificates, and also includes support for smart card authentication in more SSO application subsystems. The distribution offers the performance required to support critical workloads such as Oracle Database 12c and is available on all optimized Oracle Engineered Systems hardware and software suites based on the x86 architecture.

Oracle Linux 6.5 provides full integration with DTrace - the full-featured dynamic tracing system DTrace is now enabled by default in Unbreakable Enterprise Kernel and can be used for real-time monitoring, troubleshooting, and configuration. The distribution also supports User-Level Statically Defined Tracing (USDT) tools, which allow developers to include DTrace checkpoints in applications to configure, isolate problems and generate reports.

The updated version supports the use of Linux Containers in production environments. Linux Containers technology enables virtualization at the operating system level and works in conjunction with Linux Control Groups, allowing customers to quickly and easily consolidate workloads in a container and limit resources including memory, processors, and disk I/O. Using this technology, customers can isolate applications or OS instances on the system without overhead. Oracle VM Templates can also be used to create a container.

Oracle Linux version 6.5 also includes InfiniBand updates: enhanced InfiniBand capabilities, including the consolidation of OpenFabrics Enterprise Distribution (OFED) 2.0 protocols (such as IPoIB, eIPoIB, SRP, iSER, EoIP) and Reliable Datagram Sockets protocol (Rilts screen and firewall support), high bandwidth, high bandwidth, low bandwidth support.

In addition, new btrfs file system features allow administrators to implement an efficient incremental backup mechanism using snapshots, set different limits for volumes and subvolumes, and free up storage space using the hole punching method to designate an unused part of the file. All this complements improvements to other supported file systems, including XFS, ext4, OCFS2, ASMLib, and NFS. With the release of NFS 4.1, pNFS is now supported.

Among other features of Oracle Linux 6.5: support for Intel Ivy Bridge family processors - allows customers to use Oracle Linux on Ivy Bridge processor-based servers; Paravirtualization Drivers - Customers can run Oracle Linux as a guest operating system on Microsoft Server Hyper-V and Windows Azure using the new paravirtualization drivers. Support for NVM Express (NVMe) SSDs that can be used with Oracle Database Smart Flash Cache, the Oracle Database feature. Oracle Linux 6.5 also includes a new compatible Red Hat kernel.

Availability

The Oracle Linux 6.5 distribution is available for free download from the Oracle Software Delivery Cloud website.

2012

Unbreakable Enterprise Kernel R2

On March 23, 2012, Oracle announced the release of the Unbreakable Enterprise Kernel Release 2 kernel, based on the standard Linux Kernel 3.0.16. It provides improved memory and resource management and is optimized for virtual machine deployment. The kernel is included in Oracle Linux 5 and 6, which retain full compatibility with existing applications without the need for any modifications.

The main characteristics of Unbreakable Enterprise Kernel R2:

• Improve the performance of the task scheduler, memory management manager, file system, and network stack.

• The next-generation Btrfs file system supports up to 16 exabytes of disk storage and is optimized for solid state drives (SSDs). It is easy to administer and includes built-in data integrity control.

• Transparent Hugepages technology automatically organizes memory into larger pages to reduce management overhead and improve stability for memory-intensive applications.

• A hypervisor-enabled kernel image Xen can be used for full hardware virtualizations and paravirtualization.

Subscribers to Oracle Linux technical support services have the opportunity to try out preliminary versions (technology preview) of the DTrace dynamic tracing mechanism and OS instance isolation technology - Linux Containers.

Systems running Oracle Linux based on the presented kernel demonstrated two records at once in database performance tests. The TPC-C test DBMS in Oracle Database 11g Release 2 Standard Edition One on the Cisco UCS c250 M2 Extended-Memory Server dual-processor server showed a result of 1.05 million transactions per minute at a transaction cost of $0.58. The absolute maximum for x86 systems was recorded on the eight-processor Oracle Sun Fire X4800 M2 server (80 cores/160 threads) - 4.803.718 transactions per minute with slightly higher transaction costs of $0.98.

Notes