Ian Kent <raven@xxxxxxxxxx> writes: > On Fri, 2017-05-12 at 00:08 -0700, Andrei Vagin wrote: >> With this patch, we don't try to umount all mounts of a tree together. >> Instead of this we umount them one by one. In this case, we see a significant >> improvement in performance for the worsе case. > > Indeed, umount has been very slow for a while now. > Even a moderately large number of mounts (~10000) become painfully slow. > > Re you still perusing this? > Anything I can do to help? > > Eric, what are your thoughts on this latest attempt? I have something slightly more recent. Please checkout my for-next branch of my userns tree: git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git for-next There is one open area of semantics that I looking at with Ram Pai in the hopes we can drive consensus before we take any patches for better checkpoint-restart support. Eric
