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Marf's avatar
Marf
Icon for New Contributor rankNew Contributor
3 years ago
Solved

Intel Questasim is very slow, e.g. cd ..

Hello,

I switched from modelsim to questasim and experienced, that some questasim commands are very slow compared to modelsim. Examples are cd, project new, vsim, quit -sim...

Typing cd .. on the transcript console freezes questasim for approx 15 seconds.

One of my customers has the same problem while my FAE can simulate a project as fast as in modelsim, the cd .. takes less than a second.

Me, my customer and my FAE use the free intel questasim license, all PCs use Windows 10 (FAE has enterprise, while the other have Pro)

What we tried so far:

- install Questa Intel Starter FPGA Edition-64 2022.1 on my PC and customers PC

--> both are slow

- install Questa Intel Starter FPGA Edition-64 2022.1 on FAEs PC and an old FAE PC

--> both are fast

- install Questa Intel Starter FPGA Edition-64 2022.1 on a new Win 10 Pro VM

--> slow

For me it feels like questasim tries to access something until there is a timeout and then continues working since the delays for the slow commands is always almost the same (+- one second)

Attached you find a MeasureChangeDirDuration script, which can be started from questasim console by typing "do MeasureChangeDirDuration.txt" (.do extensions were not allowed as attachments)

How long does the "cd" command take for you?

What could be the reason for the slow behaviour?

  • Finally I found the reason for the slow behaviour.

    If I remove the intel/altera specific libraries from the default modelsim.ini, the questasim is fast again.

    Yet I didn't check, if there is a specific library or if the amount of libraries makes questasim slow. Since my code is platform independent, I removed the altera libraries from the modelsim.ini.

    Works for me and hopefully helps other FPGA developers to find a solution for this issue.

    Thanks for trying to help.

6 Replies

  • sstrell's avatar
    sstrell
    Icon for Super Contributor rankSuper Contributor

    Do you have the free license set up? Maybe it's looking for a license on the machines that are slow.

  • Marf's avatar
    Marf
    Icon for New Contributor rankNew Contributor

    Yes, I have a free license and have modified the LM_LICENSE_FILE variable. Otherwise QuestaSim would not start at all.

  • sstrell's avatar
    sstrell
    Icon for Super Contributor rankSuper Contributor

    Hard to tell what's going on. What's your installation path and is it different from the "fast" machine? Have you tried uninstalling and reinstalling? Internal or external drive installation? Other apps running? Same behavior right after a reboot? Task Manager showing anything eating cycles?

  • Marf's avatar
    Marf
    Icon for New Contributor rankNew Contributor

    Finally I found the reason for the slow behaviour.

    If I remove the intel/altera specific libraries from the default modelsim.ini, the questasim is fast again.

    Yet I didn't check, if there is a specific library or if the amount of libraries makes questasim slow. Since my code is platform independent, I removed the altera libraries from the modelsim.ini.

    Works for me and hopefully helps other FPGA developers to find a solution for this issue.

    Thanks for trying to help.

    • alexislms's avatar
      alexislms
      Icon for Contributor rankContributor

      Thanks!

      For me launching Questa takes seconds, it freezes for no reason, doing anything in the tcl console freezes the GUI for seconds.

      I contacted Intel 2years ago about it and as usual they were completely clueless.

      It's just crazy it is still not solved in 2024.

  • JackDalton's avatar
    JackDalton
    Icon for New Contributor rankNew Contributor

    Hello,

    I have the same issue.

    But I need the Intel/Altera specific libraries for my Design with Agilex 7.

    Is there another solution for that ?