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From: src@scuzzy.mbx.sub.org (Heiko Blume)
Newsgroups: comp.unix.i386
Subject: Re: ESIX tar problem (bad checksum on directory)
Message-ID: <1990Jul22.012859.24194@scuzzy.mbx.sub.org>
Date: 22 Jul 90 01:28:59 GMT
References: <5923@aplcen.apl.jhu.edu> <3162@tmiuv0.uucp>
Distribution: comp.i386.unix
Organization: Scuzzy Research Center (SRC)
Lines: 22
X-Local-Date: 21 Jul 90 18:28:59 PDT

rick@tmiuv0.uucp writes:
>>     * am I not getting full mileage out of 4 MB of RAM?

>Well, the system can't use the area between 640K and 1M, because that's where
>lots of BIOS stuff and video boards live.  That explains the "real" memory
>difference.  The "available memory" (I think) refers to the amount of free
>memory (from the "real" memory) that remains after the Unix kernal is loaded.
>I could be wrong.

correct. however it might be worth it to have a close look at the things
you can tell your chip set! older chip sets can not map the 384KB RAM
that are physically present (but unused) to addresses at the end of the
physical address space. newer chip sets like the NEAT things *can* do that.
however, you have to consider if you prefer to use shadowing your BIOS ROMs
(might be worthwhile for VGA cards? really don't know if, for example, X11
servers call the BIOS routines or talk to the cards directly) or getting some
more RAM for processes.
-- 
Heiko Blume c/o Diakite   blume@scuzzy.mbx.sub.org    FAX   (+49 30) 882 50 65
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                    "Have you bugged your source today?"