What happens when you open a DOORS Module?
This hasn't changed much since DOORS 5.x and is true through to DOORS 9.x. The DOORS server sends all the data for the current version of the module to the rich client. If the module was opened in exclusive edit mode, then it will only be available for other people to open in read only mode.
The rich client will then work through some steps before the user can start work on the module. This should take a very short time, but there are some things that users can do that will make this very slow.
Any DXL scripts that are triggered on module open will run: Triggers are dangerous when used without a complete understanding of what is happening. Module open triggers can be used to run time consuming scripts that significantly detract from the user experience.
The Default view is loaded: Any view can be set as the default view. If this contains complex Layout DXL or DXL attributes then the processing will be carried out before the user can start work and this can significantly add to module open times.
Links: No work is done on the links at module open time (unless a traceability column is included in the default view), so do not be afraid to connect up the data in your database.
Reducing module open times:
Baseline: When the module is loaded to the client, it includes all of the history since the last baseline. Baselining regularly, at appropriate points for the project, will ensure that the history is maintained in baselines, and does not slow down the module open process.
Triggers: Triggers should be used with caution and should be considered an advanced feature of DXL.
Default View: Keep this simple with no traceability columns, Layout DXL or DXL attributes.
Module size: If a module takes a long time to load, consider the size of the module. Large numbers of OLEs can take a lot of space. If you are working with a lot of OLEs, consider storing them in a configuration management tool and linking to them from DOORS rather than embedding them in DOORS. Consider splitting a module that is problematically large into multiple modules. Don't forget that deleted objects are still a part of the module; use View->Show->Deletions to see them, or Purge to delete them permanently.
Shareable Edit: Shareable edit sections slow down the opening of a module. Setting sharing at level 1 or 2 is unlikely to cause major problems assuming something like 10 to 20 sections in total. Setting sharing at level 4 or 5 with hundreds or thousands of sections is very likely to cause a noticable delay in module open times. It is also an awkward workflow to be constantly locking and unlocking sections, so people will be more inclined to open in exclusive edit for ease of use, thus defeating the intention behind shareable edit. Consider splitting the module in to multiple modules if there are multiple owners.