[pypy-dev] PyPy is much slower than CPython example / question

[Carl Friedrich Bolz]

On 07/20/2011 08:50 AM, Alexander Petrov wrote:
> So at this time I didn't come to some kind of decision about PyPy.
>
> On one hand in most of the cases with straitforward code/algorithms
> and "common" syntax constructs there was significant speed
> improvement.
>
> But on the other hand, for the cases where source Python code was
> "optimized" or "hacked" the time of execution was sometimes better,
> sometimes of one order... and sometimes was a cause for this topic
> discussion. :) It is not bad thing generally, the bad thing that this
> speed degradation situations are happenned unexpectedly for me. IMO
> they are the most (and may be only one) interesting from the PyPy-user
> viewpoint. "Where and in what cases one can expect bottlenecks". Is
> there any documented collection of such artifacts? It can be
> exceptionally useful.

Another point is that PyPy considers these programs performance bugs to 
be fixed. So the situation you describe will likely change in the 
future. Of course some perform unpredictability will always remain, that 
goes with a JIT somewhat.

Carl Friedrich