On Mon, 9 Jan 2023 at 20:30, David Holland <dholland-t...@netbsd.org> wrote: > > On Fri, Jan 06, 2023 at 10:13:36AM -0500, Greg Troxel wrote: > > Does it seem reasonably safe that mountall through root will be fast, < > 10s? > > We've been seeing scattered reports of unmounting taking fast amounts > of time, particularly on nvme devices, and I don't think we know why > yet. > > It's a bug, but since not cutting the power to SSDs midflight is one > of the primary reasons to have a UPS these days... seems like a > dangerous on in this context. So it seems like a good idea to be > cautions. > > Not sure what to recommend. The last time there was an issue like this > (which turned out to be a bad bug with cached data not being written > back until unmount time) it was possible to trigger the writing by > attempting an unmount you know will fail with EBUSY, but I don't think > we've ascertained if that works this go.
If only we had a reliable way to remount filesystems from read-write to readonly after flushing data, that could be an option on shutdown, then the ups command could be triggered with no writable filesystems :-P David
