Intel® Quartus® Prime Standard Edition User Guide: Design Compilation

ID 683283
Date 9/24/2018
Public
Document Table of Contents

2.6.6. Check if Partition Assignments Impact the Quality of Results

You can ensure that you limit negative effect on the quality of results by following an iterative methodology during the partitioning process. In any incremental compilation flow where you can compile the source code for every partition during the partition planning phase, Altera recommends the following iterative flow:
  1. Start with a complete design that is not partitioned and has no location or LogicLock region assignments.

    To run a full compilation, use the Start Compilation command.

  2. Record the quality of results from the Compilation report (timing slack or fMAX, area and any other relevant results).
  3. Create design partitions following the guidelines described in this manual.
  4. Recompile the design.
  5. Record the quality of results from the Compilation report. If the quality of results is significantly worse than those obtained in the previous compilation, repeat step 3 through step 5 to change your partition assignments and use a different partitioning scheme.
  6. Even if the quality of results is acceptable, you can repeat step 3 through step 5 by further dividing a large partition into several smaller partitions, which can improve compilation time in subsequent incremental compilations. You can repeat these steps until you achieve a good trade-off point (that is, all critical paths are localized within partitions, the quality of results is not negatively affected, and the size of each partition is reasonable).

You can also remove or disable partition assignments defined in the top-level design at any time during the design flow to compile the design as one flat compilation and get all possible design optimizations to assess the results. To disable the partitions without deleting the assignments, use the Ignore partition assignments during compilation option on the Incremental Compilation page of the Settings dialog box in the Intel® Quartus® Prime software. This option disables all design partition assignments in your project and runs a full compilation, ignoring all partition boundaries and netlists. This option can be useful if you are using partitions to reduce compilation time as you develop various parts of the design, but can run a long compilation near the end of the design cycle to ensure the design meets its timing requirements.