Ubuntu SSD Tweak
Do I have TRIM support?
To find out if you have TRIM support (not enabled or disabled), do this, it should say TRIM supported.
$ sudo hdparm -I /dev/sda | grep TRIM * Data Set Management TRIM supported (limit unknown)
Mount tmp in RAM via fstab
With sudo nano -w /etc/fstab, add line (nodiratime isnt needed as noatime susperceeds it)
tmpfs /tmp tmpfs defaults,noatime,mode=1777 0 0
- Note, Add 'noatime' mount option to stop file access time stamping
- Note, Add 'discard' mount option to SSD drive IF your drive supports TRIM (if not it is ignored anyway)
UUID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx / ext4 defaults,discard,noatime 0 0
After rebooting you should see something like this from dmesg
$ dmesg | grep "discard" [ 2.943009] EXT4-fs (sda1): re-mounted. Opts: discard,errors=remount-ro
Note, even in Ubuntu 12.04 you need to set this fstab mount option (I have seen written that you dont, but this appears to be not the case)
If TRIM is working, then the following should be 0, (assuming / is mount point of the SSD, i.e. /dev/sda mounted on /)
- Note, If just enabling and rebooting it probably wont be 0 the first time you do it.
$ sudo fstrim -v / /: 0 bytes were trimmed
Keep retrying it every few minutes when computer is in use, it should always be 0.
Tweak filesystem to stop it writing stuff
From a Live CD to keep it clean
Removing /var/log assumes you don't need logging after a reboot, which for a desktop seems fairly sensible.
Empty entirely the /tmp folder, but dont delete it, if you do by mistake remember it needs everyone to have full access to it when created. (This will still let the system work if incorrect/missing tmpfs entry in fstab)
#Clear tmp rm -rf /tmp/* rm -rf /var/tmp rm -rf /var/log #Chrome cache etc uses this by default rm -rf /home/xxxxx/.cache
Link stuff back to /tmp
ln -s /tmp /var/log ln -s /tmp /var/tmp ln -s /tmp /home/xxxxx/.cache
sudo nano -w /etc/default/grub, edit
old SSD with no trim
new SSD with trim and decent scheduler
Then run this to generate a new grub.cfg with elevator settings in.
As a one liner;
sudo sed -i 's/GRUB_CMDLINE_LINUX=""/GRUB_CMDLINE_LINUX="elevator=noop"/g' /etc/default/grub && sudo update-grub