Linux Kernel Versions

From Thomas-Krenn-Wiki
Jump to: navigation, search

The Linux core is in a constant state of development and expansion. This article will provide an overview of the most important changes to the respective versions of the core.

Important Changes

Kernel 4.13

important changes of Kernel 4.13 additional information

Kernel 4.12

important changes of Kernel 4.12 additional information

Kernel 3.11

important changes of Kernel 3.11 additional information

Kernel 3.10

important changes of Kernel 3.10 additional information
  • Bcache: The 3.10 core contains the block layer cache Bcache.
  • Timerless multitasking: Reduce the timer interrupts of the processor cores with just one step. (Dokumentation)

Kernel 3.9

important changes of Kernel 3.9 additional information

Kernel 3.8

important changes of Kernel 3.8 additional information

Kernel 3.7

important changes of Kernel 3.7 additional information
  • Release: Possibly around 11-12 / 2012

Kernel 3.6

important changes of Kernel 3.6 additional information

Kernel 3.5

important changes of Kernel 3.5 additional information

Kernel 3.4

important changes of Kernel 3.4 additional information

Kernel 3.3

important changes of Kernel 3.3 additional information

Kernel 3.2

important changes of Kernel 3.2 additional information

Kernel 3.1

important changes of Kernel 3.1 additional information

Kernel 3.0

important changes of Kernel 3.0 additional information

Kernel 2.6.39

important changes of Kernel 2.6.39 additional information
  • Support for Ip sets
  • Removing big kernel locks
  • Btrfs unterstützt Batched Discard; adjust btrfs_discard_extent() return errors and trimmed bytes
  • File system Pstore for analyzing core crashes
  • New Block Device Plugging Model for increasing scalability and performance
  • Ext4
    • Now uses Multiple Page-IO Submissions (mblk_io_submit) by default
    • Adjust minlen with discard_granularity in the FITRIM ioctl
      Discard granularity tells us the minimum size of extent that can be discarded by the device. If the user supplies a minimum extent that should be discarded (range.minlen) which is smaller than the discard granularity, increase minlen to the discard granularity, since there's no point submitting trim requests that the device will reject anyway.
  • Xen Dom0 support: network backend; see also Linux mainline contains all the Xen code bits for Dom0 and DomU support (blogs.oracle.com)
  • Distributed Replicated Block Devices (DRBDs) in the kernel is now at DRBD version 2.6.39
  • SCSI: aacraid: Add new code for PMC-Sierra's SRC based controller family (Support for Adaptec Series 6 RAID controllers, see [5] and [6])

Kernel 2.6.38

important changes of Kernel 2.6.38 additional information

Kernel 2.6.37

important changes of Kernel 2.6.37 additional information

Kernel 2.6.36

important changes of Kernel 2.6.36 additional information
  • Various performance improvements
  • AppArmor integrated into the kernel
  • KDB kernel debugger can be activated, when X-Server is used
  • Updated Out-of-Memory (OOM) killer
  • ZRam (previously Compcache) has been integrated for compressing Memory
  • Device Mapper: delay, linear, mpath and stripe targets support discards

Kernel 2.6.35

important changes of Kernel 2.6.35 additional information
  • Btrfs with direct I/O support
  • Optimization of the power-saving features for current CPUs
  • Memory compaction for reducing memory fragmentation

Kernel 2.6.34

important changes of Kernel 2.6.34 additional information
  • Ceph and LogFS file systems have been added
  • Various driver updates
  • Vhost net (for faster network to KVM & Lguest guest systems)
  • VMware ballon driver

Kernel 2.6.33

important changes of Kernel 2.6.33 additional information

Kernel 2.6.32

important changes of Kernel 2.6.32 additional information

Older Versions

Kernel Version Most Important Changes Additional Information
2.6.31
2.6.30
  • Ext4 Updates (protection against data loss during delayed allocation)
  • New drivers for audio, video and USB hardware
  • Fastboot for reducing kernel boot time
  • I2C and hardware monitoring updates
  • Notebooks: new dell-wmi driver, updates for Sony laptops and Thinkpad acpi
  • relatime Default option for file systems (instead of atime)
2.6.29
  • File system updates (Btrfs, Ext4 no journal mode)
  • Kernel mode setting (framework for controlling graphics hardware)
  • Wireless Access Point mode support
  • Wimax support
2.6.28
  • Ext4 file system – now considered stable in the kernel
  • Improvement of kernel memory management scalability
  • Disk shock protection for hard disks
2.6.27
  • Reworked WLAN drivers
  • The gspca webcam driver
2.6.26
  • New and reworked WLAN drivers
  • PCI Express Active State Power Management (ASPM) power-saving technology
  • The KGDB kernel debugger
2.6.25
  • New and reworked WLAN drivers
  • Optimizations of the Ext4 file system and the Completely Fair Scheduler (CFS)
  • The SMACK (Simplified Mandatory Access Control Kernel) security framework
2.6.24
2.6.23
  • The Completely Fair Scheduler (CFS) (process scheduler)
  • Xen DomU support (based on paravirt_ops)
  • Lguest (was originally Lguest for test purposes only, intended for paravit_ops-programming)
2.6.22
  • New WLAN stack
  • New Firewire stack
  • Support for an additional CPU architecture: Analog Devices Blackfin
2.6.21
  • High resolution timers
  • Improvements to Kernel-based Virtual Machine (KVM) including: initial para-virtualization support, live migration, CPU hot-plugging support
  • Virtual Machine Interface (VMI)[3][4][5] (based on paravirt_ops), contributed by VMware
  • A reworked ACPI subsystem
2.6.20
  • The paravirt_ops virtualization interface
  • Virtualization Kernel-based Virtual Machine (KVM)
  • Expansion of the PowerPC & Cell architectures for Playstation 3
  • IO accounting (makes the use of iotop possible)
  • Fault injection makes it possible for kernel developers to test how their code reacts to errors (kmalloc() failures, alloc_pages() failures, disk IO errors and similar errors can be simulated.)
2.6.19
  • The Ext4 file system (experimental)
  • The GFS2 file system
  • The eCryptfs file system
  • libata PATA (Parallel ATA)
2.6.18
  • libata (SATA) Update
  • CFQ is now the default IO scheduler (was already the default in many distrubiton systems like RHEL4)

References

  1. http://www.heise.de/open/artikel/Kernel-Log-Was-2-6-38-bringt-2-Dateisysteme-1192231.html
  2. http://www.heise.de/open/artikel/Kernel-Log-Was-2-6-38-bringt-4-Storage-1199339.html Kernel-Log – What Version 2.6.38 adds (4): Storage] (heise.de)
  3. How to enable Virtual Machine Interface (VMI) in a Linux kernel and in ESX Server 3.5
  4. Performance of VMware VMI
  5. Maximizing Linux Virtual Machine Performance in ESX Server 3.5 (free registration required)

Additional Information

Related articles

Linux Performance Analysis using kSar
MySQL Performance Tuning
Using Md5sum und sha1sum for Checking Downloaded Files