Re: [henshin-dev] Performance tweaks

[Riegerf@xxxxxxxxxxxxxxxxxxxxxxx]

Hi Christian,

Quoting Christian Krause <henshin.ck@xxxxxxxxx>:
> Sometimes the measured times vary a lot and it is not always  
> possible to say what caused the difference or whether a change in  
> the implementation improves the performance under different  
> conditions.
> Still, I think that we should try to improve the memory consumption [...]

Thinking about optimizations is quite nice, but seeing you are getting  
these insights from using a (on my first impression) rather  
unrealistic and made-up example, wouldn't it be much more sensible to  
use (i.e. either acquire from our users or come up with) realistic and  
more real-world examples for trying to measure and optimize performance?
I suspect that usually models are rather smaller than the Sierpinski  
example, so there might actually be no significant performance hit by  
the current implementation w.r.t. memory consumption, but some other  
aspect of the implementation could offer much better opportunities to  
work on to improve the actual speed for real-world transformation tasks.

If we want to make an effort in optimizing the Henshin Interpreter,  
actually identifying bottlenecks in the execution of the  
transformations our current users and our target user group use might  
lead to better results than just rewriting any code because of  
possible improvements this brings when using unrealistic examples.
Sadly, I am not proficient in the way the interpreter works, so I can  
not suggest anything to look at in particular. One approach may be to  
look at transformations and models our users use and find out why  
they're not as fast as they could be.

Felix