On Thu, Aug 22, 2024 at 11:45 AM David Wright <deb...@lionunicorn.co.uk> wrote:
> I'm not convinced. Finding out what needs copying back and locating > somewhere to put it is AIUI a slow process. What's much faster is > when processes themselves demand something be paged back in from > swap. I think there are "tricks" available to cause that to occur, > thus speeding up swapoff. Exactly. In my experience, running swapoff(8) _will_ take a long time if the swap area has a lot of content. It will block until everything is moved out. What I think we are seeing here is that phase has finished, but the kernel has not yet notified the backing store that it is no longer used. Though that is just a WAG. mrc
