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From: Jon Harrop <usenet@jdh30.plus.com>
Subject: Re: Heap vs Stack allocation
Newsgroups: comp.lang.ada
Date: Wed, 12 Oct 2005 02:38:16 +0100
References: <434c2709$0$21298$626a54ce@news.free.fr>
Organization: Flying Frog Consultancy Ltd.
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Date: 2005-10-12T02:38:16+01:00
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Lionel Draghi wrote:
> The paper "Java theory and practice: Urban performance legends,
> revisited - Allocation is faster than you think, and getting faster"
>
(http://www-128.ibm.com/developerworks/java/library/j-jtp09275.html?ca=dgr-lnxw07JavaUrbanLegends)
> explains (as far as I understand) how JVMs optimize "on-the-fly" memory
> allocation to use stack instead of heap, by using "Escape Analysis".
> 
> My feeling is that those writing JVMs are working hard to guess the data
> lifetime and optimize memory allocation accordingly, because the
> language is unable to express this data locality.
> I think that Ada semantics open much more opportunity to use the stack
> (or registers).

Note that OCaml allocates primarily on the heap and not the stack and is
much faster than Java.

-- 
Dr Jon D Harrop, Flying Frog Consultancy
http://www.ffconsultancy.com