Re: [wxperl-users] porting a perl/tk application to perl/wx

[Eric W. <scr...@gm...>]

# from Eriam Schaffter
# on Monday 19 March 2007 02:42 am:

>By the way, I've not done any testing of XRC performance, is it really
> as slow as Eric Wilhelm described it ?
>
>I mean is it worth using it or is the performance loss so huge that it
>really makes it un-usable .. ?
>
>Thanks for any pointers.

My observations are based on the following

  http://scratchcomputing.com/tmp/calc.pl
  http://scratchcomputing.com/tmp/calc.xrc

Comment-out the IDLE event at the bottom to have it not immediately 
exit.

  $ time ./calc.pl
  bye at ./calc.pl line 150.

  real    0m2.140s
  user    0m0.929s
  sys     0m1.167s

Then, using the dotReader testing hook, which also happens in the first 
IDLE event:

  $ time DOTREADER_TEST='print "ok\n";' ./run
  ok

  real    0m1.939s
  user    0m1.628s
  sys     0m0.182s

dotReader loads *at least* 222 .pm files in that amount of time and 
creates a gui window.  While calc.pl (stolen from a python xrc example) 
only creates a primitive calculator with 3 TextCtrls.  Using 
Devel::DProf shows that 70% of the time is spent in the (supposedly C++ 
and expat-based) Wx::XmlResource::Load method.


That      just       scares        me.


That is, however Wx 0.27 (yeah, I know, feel free to come upgrade sarge 
to etch for me and ruin my week^Wmonth while I discover everything else 
that KDE has managed to break in the last few months, deal with mozilla 
(which we *were* embedding) rolling over, etc..)  Maybe it has gotten 
better, but those numbers just scream "something is wrong" to me.

Add to that the fact that you can't even declare events in XRC, plus the 
difficulties with storing your object data in your sizer datha, plus 
the very awkward process of turning strings into integers in order to 
do anything with the objects (hey, this is Perl!  Turning my strings 
into method calls or accessors is much more useful!) and I just have to 
think chucking the whole ball of XML out the window and forgetting I 
ever heard about it is probably going to allow me to sleep better at 
night.

I'm not saying data-driven layout and configuration can't be done, but 
I'll bet XRC ain't it.  Particularly in Perl.  I can just imagine the 
if/else code that must be happening in C++ (though maybe they managed 
something involving hashes and function pointers... is "call a method 
given by a runtime string" even possible?)  In any case, the 
GetXRCID("string") stuff is rather silly.  Just watch me try to make 
any of that concise in InitMenu() of calc.pl.  Feel free to laugh at my 
pain too.  Please do show me some sympathy since I was trying to make 
this as much of a "straight and academic port" of the python code as I 
could bear.  Trust me, there a lot of "oh, man... how could anyone bear 
to write in such a verbose language as python!" and various other 
lamentations (expressed in less palatable words) involved ;-)  Heh.  
Could be worse.  We could be trying to work from wxPHP documentation!

--Eric
-- 
But you can never get 3n from n, ever, and if you think you can, please
email me the stock ticker of your company so I can short it.
--Joel Spolsky
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