RISC (Reduced Instruction-Set Chip) vs. CISC

Chris Torek torek at elf.ee.lbl.gov
Thu Apr 25 23:49:44 AEST 1991


(now why did we have `Keywords: init run level'?)

This discussion belongs elsewhere.  comp.arch would be the place to
argue over what makes something a `RISC' (it will only be the 17
million'th time the argument has gone on there).

In article <1991Apr25.033637.15092 at leland.Stanford.EDU>
fangchin at elaine54.Stanford.EDU (Chin Fang) writes:
>A good book on this is Profs. John Hennessy and David Patterson's  Computer 
>Archetectures.

Yes.

Nowadays, however, you also must be aware that `RISC' is a marketing
word, with zero meaning.  The marketeers believe that customers think
`RISC = good', so the marketeers label everything `RISC'.  (Well,
almost everything.  `RISC dinner plates, now on sale...' :-) )

>I believe many people would enjoy the chance of looking at kernel 
>disk file sizes.  Below I give three (vm)unix file sizes ...

These sizes are almost meaningless, because the size of the file tells
little about the size of the kernel.  In particular, the MIPS
executable file format typically contains two to three times as much
symbol table information (`for debuggers' is an oversimplification, but
close enough here) as some other typical formats.

For another unfair comparison (slightly more fair than raw file size),
use the `size' program:

	% size /vmunix sys/compile/ss1/vmunix
	text	data	bss	dec	hex
	868352	118000	79392	1065744	104310	/vmunix
	483328	38664	124416	646408	9dd08	sys/compile/ss1/vmunix

/vmunix is SunOS 4.1, sys/compile/ss1/vmunix is my kernel.  Mine has
almost no device drivers, and is 4BSD rather than SunOS.  I am hoping
it will shrink when I get around to cleaning some things up....
-- 
In-Real-Life: Chris Torek, Lawrence Berkeley Lab CSE/EE (+1 415 486 5427)
Berkeley, CA		Domain:	torek at ee.lbl.gov



More information about the Comp.unix.sysv386 mailing list