Budget Fair Queueing (BFQ) Storage-I/O Scheduler

• Why do I want BFQ? -Seems to speed up disk based IO see the Source section for more info.
  

http://algo.ing.unimo.it/people/paolo/disk_sched/

• First collect your existing kernel configuration.

  zcat /proc/config.gz > BFQ_CONFIG

• Next prepare your BFQ_CONFIG file (use vi or nano etc). I like to locate “CONFIG_DEFAULT_CFQ” section and make it look like below. Be careful not to have duplicate lines. I'm thinking there is a better way maybe someone could point it out. Basically add the two lines about BFQ change the existing CONFIG_DEFAULT_CFQ to “is not set” and add “CONFIG_DEFAULT_BFQ=y':

  CONFIG_IOSCHED_BFQ=y
  CONFIG_CGROUP_BFQIO=y
  # CONFIG_DEFAULT_DEADLINE is not set
  # CONFIG_DEFAULT_CFQ is not set
  CONFIG_DEFAULT_BFQ=y

• Now grab the code: (I'm using 3.14 in this sample as Slackware-current is currently using 3.14.18)

  VERSION=3.14.0-v7r6 # the version you want
  wget -nd --no-parent --level 1 -r -R "*.html*" --reject $VERSION \
      http://algo.ing.unimo.it/people/paolo/disk_sched/patches/$VERSION

• Now copy your config file to /usr/src/linux and rename it to .config
  Example: (assuming the config you created above is in your home directory)

  cp $HOME/BFQ_CONFIG /usr/src/linux/.config

• Next copy these files to /usr/src/linux and then patch (you'll want 0001 to 0003).

  cp ./000* /usr/src/linux;cd /usr/src/linux
  patch -p1 < 0001-block-cgroups-kconfig-build-bits-for-BFQ-v7r6-3.14.patch 
  patch -p1 < 0002-block-introduce-the-BFQ-v7r6-I-O-sched-for-3.14.patch 
  patch -p1 < 0003-block-bfq-add-Early-Queue-Merge-EQM-to-BFQ-v7r6-for-3.14.0.patch

• cd /usr/src/linux ;make oldconfig ;make -j4 && make modules_install

• copy bzImage and System.map to boot folder

• add lilo entry and update lilo.

• More Details here Building a Linux Kernel from Source

• Original source: http://algo.ing.unimo.it/people/paolo/disk_sched/sources.php
• Originally written by ricky_cardo
• Idea from rpi work by ponce adding bfq