The main purpose of this page is to give an overview of investigation by dichotomy.
When the log files are not enough to identify the file that is the root cause of a blocking error, or a crash, or a process that never ends, during the analysis or during the Run Metrics Calculation step, one could investigate by dichotomy to find out this file.
Please refer to official documentation about the logic of execution units : CMS+-+Working+with+Execution+Units
Release | Yes/No |
|---|---|
| 8.3.x |  |
RDBMS | Yes/No |
|---|---|
| CSS | |
Dichotomy process based on source code
In order to speed up the investigation by dichotomy, you can split the analysis unit that is failing into multiple analysis unit as described in the page CMS Analysis Unit - Information - General way to split analysis units or jobs. Each new analysis unit must be anotated with a new Execution Unit Anotation as described in the page CMS - Working with Execution Units
One of the new Analysis Unit (here A1, A2, A3) will crash, then, this Analysis Unit will be splitted also.
To make sure that the crash is focused on the "sub" Analysis Unit, Deactivate this Analysis Unit (for instance AU A3) and the parent one (Here Analysis Unit A) and run the analysis at the application level.
