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Date: Thu, 07 Aug 2008 09:38:35 +0200
From: "Ulf Wiger (TN/EAB)" <ulf.wiger@ericsson.com>
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To: peng.zang@gmail.com
Cc: caml-list@yquem.inria.fr, Ben Aurel <ben.aurel@gmail.com>
Subject: Re: [Caml-list] native vs bytecode
References: <74a4f4670808061258q30513bbdl446240feab3fdc36@mail.gmail.com> <200808061609.38758.peng.zang@gmail.com>
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X-Spam: no; 0.00; bytecode:01 hash:01 bytecode:01 ocaml:01 ocaml:01 erlang:01 kloc:01 byte:01 transitions:01 compilation:01 peng:98 peng:98 dynamically:01 dynamically:01 compile:01 

Peng Zang skrev:
> -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1
> 
> What do you mean by "dynamically load"?
> 
> You cannot mix native and bytecode generally speaking.
> 
> I don't know of any speed comparisons of OCaml bytecode.  You can
> always compile to native code, which is faster, so I don't understand
> why you would want to run anything large with bytecode.
> 
> Peng

I don't know how it is for ocaml, but in Erlang, it wouldn't be
considered strange to mix native and bytecode. The main reason
is that native code increases memory footprint compared to the
very compact bytecode. In systems with hundreds of KLOC of
code, this can make a significant difference.

There is a performance penalty when switching from native to
byte code, so one needs to try to minimize the number of
transitions in order not to cancel the effect of native
compilation.

Historically, it's been a problem that while native code
could be dynamically loaded, old code couldn't be purged
after code upgrade. I believe this problem is solved now,
or will be soon.

Again, I don't know how relevant this is to Ocaml. It was
mainly intended as an answer to the question why one would
like to mix native and bytecode.

BR,
Ulf W