Why does the Timing Analyzer GUI version 20.1 hang?

Description

Due to a problem in the Intel® Quartus® Prime Pro edition software version 20.1, you may see the Timing Analyzer hangs or slows significantly when the design contains more than 500 clocks.

Resolution

To work around this problem, perform either of the following actions:

• Use the default Timing Analysis flow instead of an interactive Timing Analyzer GUI session.

    - To prevent the Timing Analyzer GUI from opening automatically after a full compilation in the main GUI, do either of the following:

                        - In Settings->Timing Analyzer, uncheck "Enable Interactive Timing Analyzer after compilation"

                        - In the project's *.qsf file, add this assignment: set_global_assignment -name FLOW_ENABLE_INTERACTIVE_TIMING_ANALYZER OFF

• Prevent the Timing Analyzer GUI from updating in response to a new clock being created. This will mean that in dialogs with a drop-down list of clocks (such as Report Timing), the list will be empty.

    - Prevent the Timing Analyzer GUI from automatically reading SDC files by following either of these steps:

                        - In Settings->Timing Analyzer, uncheck "Automatically read constraints and update the timing netlist when project is opened"

                        - In the project's *.qsf file, add this assignment: set_global_assignment -name STA_AUTO_UPDATE_TIMING_NETLIST OFF

    - Open the Timing Analyzer GUI, and open the Tcl console (View->Tcl Console, or press Alt 2). In it, paste these lines:

                            rename tawq_register_clock tawq_register_clock_orig

                            proc tawq_register_clock {args} {}

This problem is fixed starting with the Intel® Quartus® Prime Pro Edition software version 20.3.