Name: Vladyslav Shtabovenko Date: 12/18/14-12:35:13 PM Z


Dear Feng,

I tested you code with old FeynCalc and can confirm your observations:

FeynCalc 4.2.0 pre1, Mathematica 5: 4.3 seconds

FeynCalc 9.0, Mathematica 9: 13.5 seconds

It is roughly a factor of 3 slowdown, unfortunately.

I will try to investigate this. The number of changes in the relevant
functions between Release-4_2_0_0 and Release-5_0_0_0-beta3 is not that
big so we should be able to trace the problem in a resonable amount of
tume. Git bissect is a particularly nice tool for doing this kind of
investigations.

Cheers,
Vladyslav