From 82db94b4928f4023687092a8ba1976d094a39d72 Mon Sep 17 00:00:00 2001 From: Andre Sailer Date: Wed, 11 Sep 2024 17:12:52 +0200 Subject: [PATCH] ReleaseNotes: add newlines around triple tick marks --- doc/ReleaseNotes.md | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/doc/ReleaseNotes.md b/doc/ReleaseNotes.md index 5782977af..6995648e7 100644 --- a/doc/ReleaseNotes.md +++ b/doc/ReleaseNotes.md @@ -48,6 +48,7 @@ - As reported in this issue https://github.com/AIDASoft/DD4hep/issues/1285 under certain circumstances the memory usage of DDG4 goes through the roof. This was traced back to the creation of excessive maps in the `Geant4VolumeManager`, if the number of sensitive pathes is very high like e.g. for straw detectors. - To solve the problem, geometry constructors may not declare any sensitive volumes. Hence the `Geant4VolumeManager` will not be populated. To still make Geant4 functioning, the sensitive volumes may be declared a posterior after conversion using regular expressions as implemented in the class `Geant4RegexSensitivesConstruction`. This class is only an example how such functionality may be achieved: other solutions are possible as well. This functionality can be switched at the level of each subdetector participating in the experiment setup. - To illustrate, an example detector `BoxOfStraws` was constructed with a flag in the xml description: + ``` @@ -62,12 +63,16 @@ ``` + Change `` to `` and the different behavor of memory allocation when starting Geant4 can be observed. The corresponding Geant4 python script can be found here: + ``` /examples/ClientTests/scripts/BoxOfStraws.py ``` + The memory consumption differs then as follows (depending on the thickness of the straws, which determine the number of sensitive pathes): + ``` With explicit sensitive volumes: before Geant4VolumeManager: Virtual: 903.3m resident: 690.5m @@ -79,6 +84,7 @@ after Geant4VolumeManager: Virtual: 903.3m Resident: 690.6m Simulating: Virtual: 903.5m Resident: 692.6m ``` + Hence this is a possibility to significantly reduce memory consumption for highly granular subdetectors. * 2024-07-01 Markus Frank ([PR#1287](https://github.com/aidasoft/dd4hep/pull/1287))