On Sun, 22 Dec 2019 20:06:57 +0200 Nikolay Borisov <nborisov@xxxxxxxx> wrote: > Well, if we rework how fitrim is implemented - e.g. make discards async > and have some sort of locking to exclude queued extents being allocated > we can alleviate the problem somewhat. Please keep fstrim synchronous, in many cases TRIM is expected to be completed as it returns, for the next step of making a snapshot of a thin LV for backup, to shutdown a VM for migration, and so on. I don't think many really care about how long fstrim takes, it's not a typical interactive end-user task. By all means it's great to speed it up if possible, but not via faking that with unexpected tricks of continuing to TRIM in the background. Sure, SSDs already do that under the hood, but keep in mind that SSDs are not the only application of TRIM (the other being as mentioned, thin LVs and sparsely allocated disk images). -- With respect, Roman
