Subject: Re: UBC usage-balancing code is checked in.
To: Chuck Silvers <>
From: Lennart Augustsson <>
List: tech-kern
Date: 03/12/2001 00:22:38
Could you make the freetarg and freemin variables tunable ass wel, please?

    -- Lennart

Chuck Silvers wrote:

> hi folks,
> the memory usage-balancing code that I posted about a while back
> is in -current now.  here's the log message:
>   add UBC memory-usage balancing.  we track the number of pages in use for
>   each of the basic types (anonymous data, executable image, cached files)
>   and prevent the pagedaemon from reusing a given page if that would reduce
>   the count of that type of page below a sysctl-setable minimum threshold.
>   the thresholds are controlled via three new sysctl tunables:
>   vm.anonmin, vm.vnodemin, and vm.vtextmin.  these tunables are the
>   percentages of pageable memory reserved for each usage, and we do not allow
>   the sum of the minimums to be more than 95% so that there's always some
>   memory that can be reused.
> this should fix a lot of the interactive performance problems that people
> have been reporting.  hopefully the default settings for the new sysctl
> tunables will be reasonable for everyone, but I'm sure the enterprising
> among us will want to experiment.  if anyone finds that things are
> much better with different settings, please post about it.
> as usual, let me know (or use send-pr) if there are any problems.
> -Chuck