Subject: Re: 350 pages wired down!
To: David Jones <dej@eecg.toronto.edu>
From: Michael L. Hitch <osymh@gemini.oscs.montana.edu>
List: amiga-dev
Date: 05/23/1994 21:46:21
On May 23, 11:02pm, David Jones wrote:
> But: Why do I have 313 pages wired down when in "normal" mode? That's
> 2500K of memory gone, ostensibly for purposes internal to the kernel!
>
> I am assuming that the memory occupied by the kernel itself is not
> included in vmstat's total. Even if it was, that's not sufficient
> to explain over 2 megs of internal use.
One of the things the kernel does is allocate a rather large chunk
of memory for the kernel page table pages. I think it was something
like 128 pages. I've only seen about 5 to 7 pages actually being used.
The amiga/pmap.c routine "adjusts" the number of pages allocated if
the available memory is less than 4M, since things were getting to
the point where a 4M system just wouldn't run.
> I've only 8M of core, and if I can get some of that 2M back, my machine
> would be much happier under X.
If you are building your own kernel, try changing amiga/pmap.c to
limit the number of KPT pages if there is less than 8M. That should
help somewhat.
Michael
--
Michael L. Hitch INTERNET: osymh@montana.edu
Computer Consultant BITNET: OSYMH@MTSUNIX1.BITNET
Office of Systems and Computing Services
Montana State University Bozeman, MT USA
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