1. Computers
  2. Display Drivers
  3. Graphics Cards
  4. Memory
  5. Motherboards
  6. Processors
  7. Software
  8. Storage
  9. Operating Systems


Facebook RSS Twitter Twitter Google Plus


Phoronix Test Suite

OpenBenchmarking.org

Link-Time Optimization To Speed Up The Linux Kernel

Intel

Published on 19 August 2012 12:11 PM EDT
Written by Michael Larabel in Intel
29 Comments

An extensive set of patches have been published that allow the Linux kernel to be built with GCC's LTO (Link-Time Optimization) support for generating a faster Linux kernel binary but at the cost of much greater compile times.

GCC's Link-Time Optimization support that's new in the past few years allows for inlining of functions between different files and performing various compile-time optimizations across the binary as a whole, dropping dead code, and running other checks across the entire binary. LTO'ing the Linux kernel increases the compile time by two to four times and needs 4~9GB of memory to complete.

The Link-Time Optimization Support for the Linux kernel is being done by Andi Kleen at Intel. "We see speedups in various benchmarks, but also still a few minor regressions. There's still some outstanding tuning, both in compile time and allow gcc even better optimization. Also the kernel currently triggers some slow behaviour in gcc, which will hopefully improve in future gcc versions, allowing faster LTO builds."

Aside from needing dozens of patches to the Linux kernel, the LTO support requires GCC 4.7 along with a special Linux binutils. Right now these Linux kernel LTO patches are just under a "request for comments" state but will hopefully be merged for a future Linux kernel release. It will be interesting to see how LTO'ing the Linux kernel performs as soon as Phoronix benchmarks are complete.

More details on the Link-Time Optimization support for the Linux kernel can be found in this mailing list thread. Details on GCC LTO are also available from GNU.org.

About The Author
Michael Larabel is the principal author of Phoronix.com and founded the web-site in 2004 with a focus on enriching the Linux hardware experience and being the largest web-site devoted to Linux hardware reviews, particularly for products relevant to Linux gamers and enthusiasts but also commonly reviewing servers/workstations and embedded Linux devices. Michael has written more than 10,000 articles covering the state of Linux hardware support, Linux performance, graphics hardware drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and OpenBenchmarking.org automated testing software. He can be followed via and or contacted via .
Latest Linux Hardware Reviews
  1. A Walkthrough Of The New 32 System Open-Source Linux Benchmarking Test Farm
  2. Habey MITX-6771: Mini-ITX Board With Quad-Core J1900 Bay Trail
  3. OCZ Vector 150 SSD On Linux
  4. Noctua i4 CPU Cooler: Great For Cooling High-End LGA-2011v3 CPUs
Latest Linux Articles
  1. AMD Kaveri: Open-Source Radeon Gallium3D vs. Catalyst 14.12 Omega Driver
  2. 12-Way AMD Catalyst 14.12 vs. NVIDIA 346 Series Linux GPU Comparison
  3. AMD Catalyst 14.12 Omega Driver Brings Mixed Results For Linux Users
  4. 6-Way Winter 2014 Linux Distribution Comparison
Latest Linux News
  1. KDE's Krita Loses Its Main Backer
  2. Inline Data Support Comes To CephFS With Linux 3.19
  3. VC4 Gallium3D Adds DMA-BUF Support, Yields Working DRI3
  4. GNOME Builder Is Still Building Up To A New IDE For Developers
  5. Raspberry Pi's Gallium3D Driver Could Now Run Significantly Faster
  6. CMake 3.1 Brings Windows Additions, Target Compile Feature
  7. KDE Applications 14.12 Released
  8. Fedora 21 Released For POWER & AArch64 Hardware
  9. Elasticsearch & wxPython 3 Proposed For Fedora 22
  10. The New SuperTuxKart Looks Better, But Can Cause GPU/Driver Problems
Latest Forum Discussions
  1. XLennart: A Game For Systemd Haters With Nothing Better To Do
  2. Tool for measuring FPS in games
  3. Need some hand holding with upgrading xserver
  4. Ubuntu Developers Still Thinking What To Do About Adobe Flash Support
  5. Microsoft buying Mojang
  6. Updated and Optimized Ubuntu Free Graphics Drivers
  7. Premium subscription "login" times out much faster than forum
  8. AMD Catalyst 14.12 Linux Driver Released -- Huge Update!