Instance Accelerator Files
What does File, Instance Operations do?
File, Instance Operations will save a particular instance of a part or assembly in a separate file called an "instance accelerator file" (suffix ".xpr" for a part, ".xas" for an assembly). This file is used to retrieve particular instances quickly from disk rather than having to first retrieve the generic into memory, selecting the particular instance according to the family table, and then regenerating.
Therefore, with this functionality the amount of time that it takes to retrieve an instance of a part or assembly from disk can be considerably reduced. The trade off is that more disk space will be used to store the accelerator files.
When File, Instance Operations is selected, the INST DBMS menu appears with the following options:
Inst Index - create or update the Instance Index file for a specified directory
Update Accel - create or update accelerator files for all instances currently in session
Purge Accel - examine each instance accelerator file and delete it if it is not current with the generic
SaveAccelEnv - brings up the SV INST ACC menu
When SaveAccelEnv is selected the SV INST ACC menu appears with the following options:
none (default) - the system does not save the instance in a file separate from the model.
always - the system always saves the instance in a separate file
explicit - the system saves the instance in a separate file only when the instance is explicitly saved.
The config.pro option "save_instance_accelerator" can also be used to control instance accelerator files. The values for this config.pro option are also none (default), always, explicit. When you bring up the SV INST ACC menu, one of the options will be highlighted to reflect the last setting. That setting could have been either loaded from a configuration file or selected previously from this menu.