Can fstrim work on read only mounts?

[Ahmad Samir]

On 17/08/14 10:44, Heinz Diehl wrote:
[...]
> I've read the other answers you got in this thread. I've been using
> SSD drives nearly two years, all of its partitions are mounted with
> discard enabled, and didn't encounter any sideeffects. So despite some
> folks are advising against using the discard mount option, it depends
> on what's important for you and how your system behaves. In short: you
> have to try for yourself what fits your needs.
>
> Btw: great that there's proof for at the discard mount option can
> result in lower performance. But, as always, this doesn't take into
> account if and to what degree this affects real life behaviour, which
> also varies between the respective real life situations...
>
>
>

If you can afford to leave enough free un-partitioned space on the SSD, 
then you don't need discard or fstrim as the un-partitioned space acts 
as extra over-provisioning. Have a look at this blog post[1] by Kent 
Smith from LSI (they make the SandForce flash controller on Intel SSD's) 
and the comments on it, it was very informative (for me at least).

[1]http://blog.lsi.com/gassing-up-your-ssd
-- 
Ahmad Samir