On Fri, 2019-12-20 at 17:46 +0100, Lennart Poettering wrote:
Or let me ask this differently: the "discard" mount option of various
kernel file systems, what does it differently than what this new
fedora feature is supposed to do?
fstrim does the discard once a week (or whenever it it triggered),
discard as a mount option does trigger discard when a block is freed.
Depending on the drive it may actually slow down IO as the SSD will
need more time to finish the IO. Doing an fstrim leaves the processing
to the SDD. That was the argument years ago. I don't know if this is
still true for modern SSD's. For older SSDs fstrim would stil be the
safer option. And automatic trimming is long overdue in my opinion.
Louis