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Subject: Re: [9fans] PC's 16MB SEGMAPSIZE limitations.

From: "Russ Cox" <rsc@[REDACTED]>
Date: Sat, 1 Aug 1998 15:33:54 -0400

This should be a FAQ.

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>From!owner-9fans Wed Oct 29 00:48:31 EST 1997
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Date: Wed, 29 Oct 1997 00:43:58 -0500
Subject: re: [9fans] How much memory does it require ...
Precedence: bulk

This got tossed around two years ago, and I think the
resolution was that you could change SEGMAPSIZE in pc/mem.h
and all would be fine. The two attached messages contain
the necessary bits I think.

Nigel Roles said once that 8l uses 20MB to link ghostscript
without any printer drivers.


--- forwarded messages follow ---
From!9fans-outgoing-owner Thu Nov 2 13:36:19 EST 1995
From: "G. David Butler" 
Subject: Re: 386 maximum segment size of 16Mb

I hate replying to my own mail, but I guess I wasn't finished... :-)

>The real question, has anybody looked into increasing this limit? (look
>in /sys/src/9/pc/mem.h, SEGMEMSIZE, I think, set to 16.)

Also several of the machines have this in mem.h:

#define SEGMAPSIZE 64 /* 16 is for wooses */

This would imply that all is necessary is to change 16 to 64 in pc/mem.h,
but that would be too simple...

Thanks again.

From!9fans-outgoing-owner Thu Nov 2 13:59:19 EST 1995
Subject: Re: 386 maximum segment size of 16Mb

changing SEGMAPSIZE works fine.
It incurs overhead allocated Segment structures
so 16 seemed reasonable for a terminal. We really
dont use PC's to compile.