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

Linux Kernel Gets Hot-Data Tracking

Linux Kernel

Published on 10 October 2012 10:27 AM EDT
Written by Michael Larabel in Linux Kernel
5 Comments

Patches continue to be developed for the Linux kernel that provide hot-data tracking support for file-systems. This hot-data tracking feature may lead to performance improvements when dealing with commonly used data on the disk. Currently this feature has been developed with Btrfs in mind, but could be adapted to other Linux file-systems.

The VFS hot-data tracking patches are now up to their third revision. While the Linux 3.7 merge window is currently open, the hot-data tracking patches are not quite ready yet with still a TODO list of eight items open after the v3 patches were published. It looks like hot-data tracking will burn the Linux 3.8 kernel at the earliest.

Linux kernel hot-data tracking is for tracking data "temperature" information in the VFS layer. The Linux kernel VFS layer stores some statistics like the number of reads/writes, last read/write times, read/write frequency, etc. Those various data points are then turned into a single data "temperature" to determine what data on the disk is "hot" -- i.e. the most used data on the disk. The hot data can then be moved to a solid-state drive (SSD) automatically or dealt with in other manners. The long-term development goal is for allowing Btrfs to intelligently use SSDs in a heterogeneous volume. Btrfs has long desired hot-data relocation and now it's finally coming to reality.

While the initial patches implement hot-data tracking only for the Btrfs file-system, with a bulk of the hot-data work being done in the VFS layer, other file-systems could tap into this feature too. With all the patches applied, the Btrfs file-system needs to be mounted with a hot_track mount option for the feature to be actually flipped on. Hot-data statistics are also exposed over debugfs.

The patches for those interested can be found on the kernel mailing list.

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. Civilization: Beyond Earth Linux GPU/Driver Benchmarks
  2. X.Org Server 1.16.3 Released To Fix Security Issues
  3. Linux 3.19 Merge Window Closes Ahead Of Schedule
  4. MIPS R6 Architecture Now Supported By GCC
  5. LowRISC To Feature Tagged Memory & Minion Cores
  6. Intel Skylake Audio Support For Linux 3.19
  7. After 10+ Years, NetworkManager Reaches v1.0
  8. VDPAU Updated To v0.9
  9. An Open Hardware Random Number Generator Proposed
  10. LLVM 3.6 Will Be Branched Next Month
Latest Forum Discussions
  1. Need some hand holding with upgrading xserver
  2. Are there an app using HSA ?
  3. The New SuperTuxKart Looks Better, But Can Cause GPU/Driver Problems
  4. XLennart: A Game For Systemd Haters With Nothing Better To Do
  5. Updated and Optimized Ubuntu Free Graphics Drivers
  6. Debian init discussion in Phoenix Wright format
  7. FPS capped on Linux (AMD fglrx drivers)
  8. Bench specific mount point