RE: conditional compilation of debug facilities in LUA core

[Benoit Germain <bgermain@...>]

I am not working in an environment where the measures I could do are
significant (W2K, to name it). Also, measures on an intel-based system with
a few hundred Kb of L1 cache might not provide information as to the gain we
get, say, on a R5900 core with 8K of L1 code cache :-)
And I haven't yet had the time to do it, but I am going to take it real
soon.

Cheers,

Benoit.

> -----Original Message-----
> From: Jani Kajala [mailto:jani@sumea.com]
> Sent: vendredi 6 septembre 2002 19:34
> To: Multiple recipients of list
> Subject: Re: conditional compilation of debug facilities in LUA core
> 
> 
> Hi,
> 
> Have you profiled the difference in your application? How much more
> performance you get by removing the debug stuff?
> 
> 
> Regards,
> Jani Kajala
> 
> ----- Original Message -----
> From: "Benoit Germain" <bgermain@ubisoft.fr>
> To: "Multiple recipients of list" <lua-l@tecgraf.puc-rio.br>
> Sent: Friday, September 06, 2002 5:10 PM
> Subject: conditional compilation of debug facilities in LUA core
> 
> 
> > Hi all (well, game developers might be more specifically 
> concerned, I
> think)
> >
> > I was thinking that when using LUA as a scripting extension 
> for a game,
> once
> > the scripts are debugged they will not change, because the scripting
> engine
> > won't be exposed to the player (unless you use LUA as a 
> console language).
> > In that case, all the debug stuff is no longer necessary, 
> as well as the
> > hook mechanism. Therefore, in order to make LUA leaner and 
> faster, it
> might
> > be interesting to be able to compile the core with all this being
> disabled.
> > Of course the setjmp/longjmp mechanism should remain, but 
> testing for a
> > count hook at each VM instruction, and keeping lua_Debug structure
> pointers
> > in some places is something I would want to be able to control, for
> example
> > by commenting out a -DLUA_REFLEXIVEDEBUG directive in the 
> config file...
> >
> > I guess this shouldn't be too much work for anybody, but if 
> this could
> > become a feature of the official lua distribution, it would 
> spare many of
> us
> > the throes of despair at not having found all the places to 
> touch, and of
> > doing all this all over again when upgrading.
> >
> > I suppose that it would mean that the associated compiler 
> would be unable
> to
> > generate unstripped bytecode files, and that a virtual 
> machine without
> debug
> > facilities would have to fail gracefully upon being handled 
> a precompiled
> > file with debug infos (even if crashing would'nt bother me 
> too much).
> >
> > Anybody with me to convince the authors to include this 
> feature in 5.0
> final
> > :-) ?
> >
> > Cheers,
> >
> > Benoit.
> >
>