Why are these using swap when I have plenty of free ram?

[Colin Watson]

On Fri, Nov 08, 2019 at 10:19:15PM +0000, Colin Law wrote:
> On Fri, 8 Nov 2019 at 21:44, Chris <chris.pollock1948 at gmail.com> wrote:
> > The below processes are using swap for some reason:
> 
> If you have a transient situation with a shortage of RAM then little
> used stuff will be moved out to swap. When the transient situation is
> over there may be plenty of RAM available but if the stuff in swap is
> not used again then it will be left there.  There is no reason to go
> to the effort of moving it back.

In a similar way, it might even be not because of any particular memory
pressure, but because using RAM to cache things read from disk was more
valuable than keeping the memory of rarely-used processes in RAM.

-- 
Colin Watson                                       [cjwatson at ubuntu.com]