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Altera_Forum's avatar
Altera_Forum
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12 years ago

Very Slow when simulation Cyclone V UniPHY funtional model

Hi everyone,

Environment : WIN7 64bits, Intel i5-3470 CPU with 6GB RAM, Quartus II 13.0 with Modelsim-AE installed.

Now I have completed a design with Cyclone V UniPHY DDR3 interface and I need to simulate in modelsim to check the logic correctness. While I find the simulation speed is very slow. When I simulate the whole design, the speed is only about 0.5us per second. And in order to check whether the slow down is caused by my code, I generate the UniPHY core with example design, which already provides a sample testbench and modelsim simulation script. I used these "official" settings and find the speed is about 1.0us per second, which is not good enough. Since I need to simulate a whole video frame, so I need a simulation time of about 40ms, and I have already consumed over 100 hours to get a result.

I have complete a design with Xilinx device serveral months ago, also with a MIG based Spartan 6 DDR2 interface, and with the whole complex design(not only the controller), I can achieve a speed of about 4us per second on the same machine.

Is there some options I am missing? Or the simulation speed is just like that?

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    I partially resolved this problem. I changed the simulator from Modelsim-Altera 10.1d to Modelsim 10.2 and the simulation speed increased to about 2us per second. This is not good enough but is more or less acceptable in practice.

    I think the altera guys should pay more attention to improve the simulation model.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    Are you logging all signals to the waveform database? You should try an experiment to see what the best possible performance would be if you logged no signals. Then you may need make tradeoffs in performance by selecting only a restricted set of signals to log.

    Are you running interactively or in non-gui command line mode?

    Depending on which edition of Modesim 10.2 you have, there may be other options for optimizing and profiling your design. You should look at the Modelsim User Guide.