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From: dewar@merv.cs.nyu.edu (Robert Dewar)
Subject: Re: Beware: Rep spec on an enumeration type causes code explosion
Date: 1997/12/10
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Joe said

<<As I said in my reply to Tucker Taft, our experience is that only
fixed-block allocators work in embedded realtime, especially when the
system is heavily loaded.  Such allocators have constant performance,
right up to the point of pool exhaustion, and recover instantly when
someone returns some memory.  Variable block allocators as a class run
slower and slower as their pool approaches exhaustion; this is exactly the
wrong behaviour, as it makes worse the effects of the original overload.
>>

This is an over-generalization, there are algorithms known that provide
variable size allocation with constant performance. These algorithms are
the ones that should be used for real time performance.