Re: Linux compat and swap

[tlaronde%polynum.com@localhost]

On Thu, Apr 23, 2020 at 11:56:08AM +0100, Sad Clouds wrote:
> On Thu, 23 Apr 2020 10:56:15 +0100
> Mike Pumford <mpumford%mudcovered.org.uk@localhost> wrote:
> 
> > If you have both memory intensive and filesystem intensive processes 
> > running on a NetBSD system the kernel filesystem cache can end up 
> > evicting programs running in the background that are inactive which
> > then take a LONG time to recover. For a system with a reasonable
> > amount of memory I found the vm.filemin and vm.filemax needed to be
> > tweaked so that filesystem cache was more likely to be tweaked than
> > program code.
> 
> Is this correct? I always thought that file cache was opportunistic,
> i.e. it will use all free memory, but under no circumstances it should
> evict any pages of running programs. The opposite should happen, i.e.
> any program using memory should be allowed to steal it from file cache
> at any time.

That was what I thought but I was obviously wrong since the program was
killed when there were still 2G of memory allocated for file caching...

This is why I said "still enough RAM": the memory for file caching was
available, in my mind...
-- 
        Thierry Laronde <tlaronde +AT+ polynum +dot+ com>
                     http://www.kergis.com/
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