Can fstrim work on read only mounts?

[Heinz Diehl]

On 17.08.2014, Ali Alipoor.R wrote: 

> 1- can fstrim work on read only mounted partitions?

No. On partitions mounted "ro", nothing gets deleted, and thus there
is no need for discard.

> 2- can discard and ro options be mixed in fstab?

Yes, but this makes no sense.

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...