Subject: Re: Limiting memory usage of bufcache?
To: Matthias Buelow <>
From: Wojciech Puchar <>
List: netbsd-users
Date: 08/24/2001 08:27:04
> have observed in an earlier version (dunno if it's still doing it) of
> writing out its filecache pages to the swapfile.  If NetBSD is actually
> paging out active pages to make room for the buffer cache, this is a
> horribly serious bug and should be fixed ASAP!  The buffer cache must

just like linux. when i first installed netbsd 1.5 i found it's much
better with static buffer cache just because of that.

> always have a lower priority than user-space mapped pages and only use
> completely unmapped memory pages which are unused otherwise (it shouldn't
> even harrass the "inactive" pages of recently mapped but now unmapped
> user pages.)
no so. i some case with 100% memory usage by programs of which 1% were
unused for 5 hours there is a sense to page out this 1% and make space for
buffer cache.

i think easiest fix would be to make it lower priority and multiply it's
pages age by hundred or so when selecting page to swap.