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====== Using a SSD as Boot Device ====== If you are lucky enough to have a SSD drive available as boot device you'll certainly want to use it.\\ One important fact to know about SSDs is that you need to "clean" them on a regular basis to maintain top performances. This is done using the TRIM command: TRIM allows the OS to "inform a solid-state drive (SSD) which blocks of data are no longer considered in use and can be wiped internally". Without using TRIM, the SSD speed decreases after a while so if you have a solid-state drive that supports TRIM, you should enable it so your SSD remains fast over time. ===== Determine if Your SSD supports TRIM ===== You first need to make sure that your SSD supports the TRIM command, to do that use the following commands: <code> sudo hdparm -I /dev/sda | grep "TRIM" </code> You might have to use another device identifier than// /dev/sda// for you it might be// /dev/sdb// or// /dev/sdc//. To get your disk identifier, use: <code> sudo fdisk -l </code> ===== fstab or cron ? ===== ==== Online discard in fstab ==== Although using online discard (in fstab) seems to be **NOT RECOMMENDED**, in case you really want to use this technique, open /etc/fstab as root with a text editor: <code> sudo nano /etc/fstab <code> And add the "discard" option (separated by a comma and no space!) to the SSD partitions you want to enable TRIM for. Here's an example: <code> <file system> <mount point> <type> <options> <dump> <pass> # / was on /dev/sdb1 during installation UUID=1cd2fc4f-7d99-4c7a-8ea7-6f9a2d5e5960 / ext4 discard,errors=remount-ro 0 1 </code>