Path: utzoo!attcan!uunet!lll-winken!lll-lcc!ames!mailrus!husc6!mit-eddie!killer!walls
From: walls@killer.UUCP (Monty Walls)
Newsgroups: comp.os.minix
Subject: malloc.c
Keywords: malloc.c memory
Message-ID: <4208@killer.UUCP>
Date: 28 May 88 01:44:56 GMT
Organization: The Unix(R) Connection, Dallas, Texas
Lines: 24


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	Recently while profiling a peephole optmizer I use on my system
I noticed that 30% of the program's time was being spent in the malloc.
This is probably the case in any program that does lots of malloc calls.
I replaced the standard malloc.c that came with minix with the one in
the back of 'K & R'.  This dropped the profiled usage of malloc.c to 2%
of the programs time.  Also because minix malloc is using 16 byte aligmnent
and using 16 byte chunks, you get memory fragmentation and an excessive
number of system calls for memory.
	I have looked at the minix malloc and I really am not 
comfortable with my understanding of it.  So I could be introducing a new
set of bugs by using 512 byte chunks aligned on word boundaries.  I
would appreciate it if other people would look in to this and see if
my observations are correct.

-Monty Walls


Monty Walls
MIS Division, Tech. Support
Oklahoma Tax Commission
2501 N. Lincoln
OKC, OK, 73194