Some performance notes

[Rob Gayvert]

Steven Swerling wrote:

> Hi,
>
> Today I decided to look into the relation between build settings and 
> performance as measured by tinyBenchmarks.
>
> First I just tried building a release version of wxsqueak with msvc's 
> compiler optimized for speed (btw, rob, I believe your Release build 
> settings do not optimize for speed).
>
> I ran one of my wxsqueak.image on a variety of VMs, and got the 
> following results:
>   stock squeak.exe (squeak 3.7)
>       '218,057,921 bytecodes/sec; 6,830,576 sends/sec'
>   my release SPSwxsqueakFAST.exe (compiler optimized for speed)
>       '115,732,368 bytecodes/sec; 5,726,364 sends/sec'
>   debug wxsqueakd.exe
>       '54,794,520 bytecodes/sec; 2,581,531 sends/sec'
>   standard wxsqueak.exe
>       '53,377,814 bytecodes/sec; 2,507,017 sends/sec'
>
> So just flipping the "optimize" bit gets bytes/sec halfway there, and 
> sends/sec almost home.
>
> I then replaced the vm sources with the original 3.7 vm sources (from 
> sourceforge), but still got 115M bytes/sec from the build. So I 
> decided to build using the "build.bat" file that uses gcc, but w/out 
> the WXPlugin. This build got me the full performance (218M 
> bytecodes/sec). Note that this gcc build was on the same sources I 
> with which I had just built with MSVC -- it just yields a faster 
> executable.
>
> This all suggests that perhaps getting WxPlugin to compile using the 
> standard make tools might net a little performance increase. Or 
> perhaps that there is some hidden compiler flags for msvc that will 
> speed things up.

Yowser. That's more than a little increase. I get very similar numbers 
on my box for all four cases. But this is good news.  It's not often you 
can get a 2x or 4x speedup with so little effort. For now, I'll at least 
change my release version settings to get the 2x increase. Later, I'll 
move over to the gcc build.