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Re: performance


Doug Evans <devans@cygnus.com> writes:

 >    From: Mikael Djurfeldt <mdj@nada.kth.se>
 >    Date: 22 Mar 1999 21:01:42 +0100
 > 
 >    Personally, I almost never need the extra speed but I'm often glad to
 >    get backtraces, so I'm happy about the debugging evaluator being the
 >    default one, but you have a point anyway.  It's probably many people
 >    who just make a quick test and find it slow...
 > 
 > I like the debugging evaluator as the default too (fwiw).
 > 
 > guile prints (or use to print) something like
 > "Do (debug-enable 'backtrace) if you want to automatically see backtraces."
 > in error output.
 > 
 > Maybe at the start of an interactive session it could also check
 > if the debugging evaluator is active and if so print something like
 > "Do (debug-disable 'debug) if you want to do performance tests."
 > or whatever.

I think it's insane to ship it with debugging turned on for the
following reasons:

1. The thing has enough performance problems without adding to it.
2. Haven't we seen enough messages of the form "I tried out guile but
   it was so slow that I decided to use XXXX instead?"
3. Most people are going to be just using guile because it's built
   into some application.  They're not going to be writing
   applications.  Why should the bulk of the user population suffer
   for the developers given:
4. The developers can put (debug-enable 'debug) at the top of the code
   they're working on.  For that matter, if debugging off were the
   default, they could do something like detect whether or not the
   code is run as a script or is loaded into a running guile
   interpreter & turn on debugging in the latter case.
5. For that matter *why* is the debuggging interpreter 3-4x slower than the
   nondebugging one?!?!?  TCL & STk give tracebacks on error and I've
   verified that STk is competitive with scm in speed, let alone with
   guile with debugging *off*!

-- 
Harvey J. Stein
BFM Financial Research
hjstein@bfr.co.il