problem with parallel foreach

[Ali Çehreli via Digitalmars-d-learn]

On 05/12/2015 07:59 AM, Gerald Jansen wrote:

 > the performance of my D version deteriorates
 > rapidly beyond a handful of jobs whereas the time for the Python version
 > increases linearly with the number of jobs per cpu core.

It may be related to GC collections. If it hasn't been changed recently, 
every allocation from GC triggers a collection cycle. D's current GC 
being a stop-the-world kind, you lose all benefit of parallel processing 
when that happens.

Without seeing runJob, even arr2.dup may be having such an effect on the 
performance.

Ali