On 16 May 2014 17:11, Russell Coker <russell@coker.com.au> wrote:
https://en.wikipedia.org/wiki/TRIM
The TRIM command can theoretically improve performance in some situations. However it also significantly decreases performance in other situations. So for a typical use with BTRFS it's recommended that you not use it.
Note that when the SSD erase list gets fragmented such that TRIM helps will depend on work load. It could happen in a matter of days or not happen in a year. Also it would depend on the quality of the SSD.
Don't use the discard mount-options because, as you mention, it can decrease performance in the moment. The preferred solution is to run 'fstrim' automatically in an off-peak time, eg. the middle of the night. It'll discard all the unused blocks in one go.