GNU Emacs, memory usage, releasing

Peter da Silva peter at ficc.uu.net
Mon Jan 1 11:01:43 AEST 1990


In article <32534 at news.Think.COM> rlk at think.com (Robert Krawitz) writes:
> 2)  Emacs dies very quickly after its virtual size exceeds 16 Mbytes,

This is a scary thought all by itself, but...

> due to the 24 bit pointers used (the top 8 bits are used as tag bits for
> the Lisp interpreter).

Come *ON*, why is this accepted? I remember not so very long ago people were
flaming Microsoft for doing this on the Macintosh, which led to Microsoft
applications not working on >1MB machines after the extra bits started getting
decoded...

Not to mention that making assumptions about pointer formats is dangerous in
and of itself. Certainly you can't *use* such pointers without stripping them,
which adds overhead to every memory reference. And (per recent discussions
in comp.std.c) there are architectures out there that won't even let you load
them into an address register.
-- 
`-_-' Peter da Silva. +1 713 274 5180. <peter at ficc.uu.net>.
 'U`  Also <peter at ficc.lonestar.org> or <peter at sugar.lonestar.org>.
"It was just dumb luck that Unix managed to break through the Stupidity Barrier
and become popular in spite of its inherent elegance." -- gavin at krypton.sgi.com



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