SSD optimizations on Linux

• Use the mount option relatime (or noatime if you are brave) for the SSD partitions in /etc/fstab.
• Replace several directories (those, the system writes to frequently) with a tmpfs file system as shown below.
• Disable Firefox caching by setting browser.cache.disk.enable to false in about:config.
  Alternatively create the entry browser.cache.disk.parent_directory and set it to /tmp.
• Tell grub2 to boot the kernel without optimisation for regular HDDs by adding elevator=noop to the GRUB_CMDLINE_LINUX_DEFAULT= parameter in /etc/default/grub. Afterwards run sudo update-grub2.
  If you want to use the elevator deadline (not noop) you may enable the fifo_batch for sda: echo 1 > /sys/block/sda/queue/iosched/fifo_batch
• Try write-back caching instead of write-through by running hdparm -W1 /dev/sda. If this succeeds add it to /etc/rc.local.
• Disable hibernation (writes large amounts of data to the SSD): See above.

Append this to /etc/fstab in order to replace /tmp, /var/tmp and /var/log with ramdisk folders:

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# mount /tmp to ram (tmpfs)  
tmpfs   /tmp   tmpfs   nodev,nosuid,noexec,relatime,mode=1777,size=15%    0    0
tmpfs    /var/tmp    tmpfs    defaults,size=5%    0  0
tmpfs    /var/log    tmpfs    defaults,size=5%    0  0

But you also need to recreate some folders (in order for some programs to be happy). So add the following script in your /etc/rc.local just above exit 0:

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#!/bin/sh
# you may want to add more folders to be checked/created to this list:
for dir in apparmor apt ConsoleKit cups dist-upgrade fsck gdm installer news ntpstats samba speech-dispatcher unattended-upgrades; do
  if [ ! -e /var/log/$dir ] ; then
    mkdir /var/log/$dir
  fi
done

To disable hibernation completely, tell Policy Kit hibernation is forbidden for all users:

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cat << EOF | sudo tee /etc/polkit-1/localauthority/50-local.d/02-disable-hibernation.pkla
  [Disable hibernate/suspend for all groups]
  Identity=unix-group:*
  Action=org.freedesktop.upower.hibernate
  ResultActive=no
  ResultInactive=no
  ResultAny=no
EOF

resources

• main resource: http://opentechnow.blogspot.com/2010/02/linux-ssd-optimization-guide.html
• more on tmpfs mounts: http://forums.debian.net/viewtopic.php?t=16450
• tips for Windows (might serve as an inspiration):http://thessdreview.com/optimization-guides/the-ssd-optimization-guide-2/
• great resource on SSDs with Linux: https://wiki.ubuntu.com/MagicFab/SSDchecklist
• fifo_batch: http://ubuntuforums.org/showthread.php?t=1464706
• http://www.ocztechnologyforum.com/forum/showthread.php?54379-Linux-Tips-tweaks-and-alignment&p=598608&viewfull=1#post598608
• https://help.ubuntu.com/community/AA1/Using#line-5
• Forbid hibernation using PolicyKit: https://bugs.launchpad.net/ubuntu/+source/policykit-1/+bug/621416/comments/5
• Presentation on SSDs on Linux (German)

Related Posts:

• Installing Arch Linux On An Asus EEE PC 900 Netbook
• Update the Firmware of an OCZ Agility 3 SSD via the Linux Command Line
• SSD Optimizations on Mac OS X
• Installing Ubuntu 10.10 Netbook Edition on Asus eee PC 900