On Tue, Mar 22, 2022 at 01:00:42PM -0500, Nicholas Geovanis wrote: > That's the usual issue. The /tmp filesystem is usually configured to live > in RAM,
That's not the default in Debian. Of course, it might have been set up that way on the OP's system. > at some point an application needed to use lots of it. It may not have > freed it properly > from dying or maybe it's still running, or just misbehaving :-) When an application terminates, all of the memory that it used for private variables and such gets freed, and becomes available to other processes. However, this doesn't cause swapped-out pages belonging to other processes to be swapped back in. So, for example, immediately after closing a web browser that was using gobs and gobs of memory, you might see that the "used" memory drops dramatically, and "free" memory grows. But the amount of swap being used won't change immediately. Swap space is used primarily (or ideally) by *inactive* processes. It won't be released until one of those processes wakes up and needs the data that has been swapped out. Or until one of those inactive processes terminates, at which point all of its swap usage is released. (When swap is used by an *active* process, that's called thrashing. At that point, you're in trouble.)
