Home > Linux, Linux 3.0 > Linux 3.4 Release

Linux 3.4 Release

Linus Torvalds has just announced the release of Linux Kernel 3.4 on the 20th of May:

I just pushed out the 3.4 release.

Nothing really exciting happened since -rc7, although the workaround for a linker bug on x86 is larger than I’d have liked at this stage, and sticks out like a sore thumb in the diffstat. That said, it’s not like even that patch was really all that scary.

In fact, I think the 3.4 release cycle as a whole has been fairly calm. Sure, I always wish for the -rc’s to calm down more quickly than they ever seem to do, but I think on the whole we didn’t have any big disruptive events, which is just how I like it. Let’s hope the 3.5 merge window is a calm one too.

Linus

Linux 3.3 merged Android drivers to mainline, added further improvements to btrfs and ext-4 file systems, several networking features and improvements (Open Vswitch, bufferbloat limitations…), Texas Instruments C6X DSP support and EFI boot support.

Linux 3.4 brings the following key changes:

  • Btrfs Updates: 
    • Repair and data recovery tools: btrfs-restore + better fsck
    • Metadata blocks bigger than 4KB
    • Performance improvements: The throughput is now much more constant. See file creation test in 3.3 vs 3.4. The same test that previously took 354 seconds, now takes 204 seconds.
    • Better error handling.
  • GPU Drivers:
    • Early support of Nvidia GeForce 600 ‘Kepler
    • Support for AMD RadeonHD 7xxx and Trinity APU series
    • Support of Intel Medfield graphics
  • New X32 ABI: 64 bit mode with 32 bit pointers: The ability to use 32-bit pointer is 64-bit mode allows the higher performance of 64-bit mode together with the smaller footprint of 32-bit pointer.You can check the presentation slides for details.
  • x86 cpu driver autoprobing: Linux adds auto probing support for cpu drivers, based on the x86 cpuid information, in particular based on vendor/family/model number and also based on CPUID feature bits. This solve a loading failure with SSE 4.2 accelerated CRC module which can significantly boost (once it’s loaded) the performance of BTRFS.
  • Support for external read-only device as origin source of a thin provisioned LVM volume: One use case for this is VM hosts that want to run guests on thinly-provisioned volumes but have the base image on another device.
  • “perf” tool improvements:
    • GTK2 report GUI perf report – It can be launched with ‘perf report –gtk’
    • Better assembly visualization – ‘perf annotate’ has visual improvements for assembly
    • Hardware based branch profiling – Some CPUs can support this feature (x86 Intel CPUs with the ‘LBR’ hardware feature) and this is support in perf. Command line: ‘perf record -b’
    • Filtering of users and threads – Filter users with ‘–uid’ parameter and processes & threads with ‘-p’ and ‘-t’ parameters.
  • Yama’ security module:Yama is a new security module (like selinux, apparmor…) that collects a number of system-wide DAC security protections that are not handled by the core kernel itself.
  • QNX6 filesystem: Read-only support for qnx6fs used by newer QNX operating system versions such as  Neutrino.

Further details on Linux 3.4 are available on Kernelnewbies.org.

Digg This
Reddit This
Stumble Now!
Buzz This
Vote on DZone
Share on Facebook
Bookmark this on Delicious
Kick It on DotNetKicks.com
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter