On 7/11/2017 11:23 AM, Josh Triplett wrote: >> There are two main methods for doing this, synchronously using the >> "discard" mount option or asynchronously using fstrim [2]. Colin King did >> some extensive benchmarking and found that on desktops and servers you >> usually want a cron'ed fstrim [3]. > > This assumes that you can handle a disk-heavy job running via cron, > rather than distributing the overhead over time. (That link mentions > fstrim running for a long time even when run on a daily basis, let alone > weekly.) Sometimes you want to maximize peak performance at the cost of > extra overhead at specific times; sometimes you want consistent > performance and no downward spikes. > > Ideally, I would suggest that we start enabling the "discard" option by > default in d-i. That would also avoid spinning up a periodic cron job > that runs regardless of actual need or disk activity. > > (One of the things I really wish we could do more easily is eliminate > the numerous cron jobs that simply wake up, realize they have no work to > do, and go back to sleep.)
I assume that since this bug is still open in Debian, that Ubuntu diverged here since we've had the fstrim cron job for a few years now. I even came across a bug report not too long ago saying that it trashes OCFS filesystems running on a SAN.
