@gavrilen has done code improvements to speed up the Pixel Space Point formation by about a factor 4-5 in 20.20 with ttbar events at 200 pileup. These improvements, already ported to 21.9, are now ported to master.
The main changes are:
- evaluation of the cluster global position and covariance multiplying directly quantities of its local position and covariance. This avoid evaluating the cluster global position using
clus->detectorElement()->surface().localToGlobal(clus->localPosition())which is very time consuming. - implementation of a new constructor for
PixelSpacePointto use directly the global position and the covariance evaluated as mentioned above.