Default: 7.25s
All off: 0.11s
EC+EC1 off: 7.02s
CC+SC off: 6.64s
DC off: 6.68s
TORU off: 8.31s (checked again)!
FOIL off: 2.47s
MINI off: 3.91s
FOIL+MINI off: 2.63s
There are some weird results here. I am not sure if turning off the
MINI section turns off the corresponding magnetic field as well. Anyone know?
Also - the number printed out at the end of a GSIM run changes significantly if
other processes are using the CPU at the same time. I don't think it is CPU
time, though I suppose it could be if other resources are the bottleneck.
Anyway, I try not to tax my computer while making a measurement, but small
cahnges could happen due to that.
When combined with what I saw before (most of the calls to gtnext are from the
DC volume), this implies that our biggest time sink is particles showering
in the shielding foils, which we then track through the rest of the detector.
I am not certain how the shower libraries are being designed, but if they are
only for the EC's, it is not clear they will save significant time.
If a particle showers in the FOIL, or in any other volume (even including the
EC's I think), we no longer need to track the resulting particles with the full
precision that we use for `pristine' particles. We will already have lost
significant resolution from the energy collection and the fact that we lose
momentum in unconverted gammas. I don't know how to make this change, but it
must be possible....
-David Rowntree