Stats

  • Locked Locked
  • Replies 4
  • Subscribers 124
  • Views 1899
  • Members are here 0
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Got Stuck in Harmonic Balance Analysis

MarcoL

Hi all,

       Recently I needed to run a lot of hb analyses but always got stuck in the processing.  

      Not saying hb would not work, but it generally takes much more time than I expected. So I looked into the output log while monitoring the CPU utilization of spectre. Here is the problem I found.

     DC and AC analyses were run before HB, and both seemed to work well with a CPU utilization of around 400%. So I thought computing resources were abundant and thus expected HB analysis to utilize more computing resources to move faster. However, it turned out HB got stuck between "Important HB parameters" and "initial residual" for plenty of hours, while the CPU utilization fell down to 100% or less. It's like:

   Important HB parameters:

   RelTol = 1.00e-3

   abstol(I) = 1.00e-12 A

  abstol(V) = 1.00e-6 V

  residualtol =1.00e+00

  lteration = 3.50e+00

  steadyration =1.00e+00

 maxperiods =100

( Here spectre got stuck for plenty of hours, not even bother to move! )

**initial residue**

     I am not sure whether or not it's common; Worse, no idea attained after I consulted the local Cadence AE. She checked my settings and said there was nothing wrong. "Maybe it has something to do with the host machine", she said.

  So does anyone know what spectre is doing where it gets stuck in my case? Any solutions?

  By the way, I am using IC6.1.6-64b.500.10 and spectre 15.1.0.345.isr2.

Thanks a lot!

Marco

2016.12.02

Parents
  • MarcoL
    Hi Andrew,

    Thanks for your reply.
    I guess that's all we can do here. As long as the analysis can finally disgorge some results, no matter how long it would take, we would choose to put up with it and then forget it. Involvement of different guys from two companies may be a much larger project than a single simulation.
    I posted out the issue just hoping to see whether or not you guys may have a clue, since you guys look sooooooo erudite, not really depending on a direct solution. You have done much more than I expected and sincerely thank you sir.
    Maybe sometime later I would somehow resolve the problem, in which case I would post it here.

    Regards,
    Marco.
Reply
  • MarcoL
    Hi Andrew,

    Thanks for your reply.
    I guess that's all we can do here. As long as the analysis can finally disgorge some results, no matter how long it would take, we would choose to put up with it and then forget it. Involvement of different guys from two companies may be a much larger project than a single simulation.
    I posted out the issue just hoping to see whether or not you guys may have a clue, since you guys look sooooooo erudite, not really depending on a direct solution. You have done much more than I expected and sincerely thank you sir.
    Maybe sometime later I would somehow resolve the problem, in which case I would post it here.

    Regards,
    Marco.
Children
No Data

Community Guidelines

The Cadence Design Communities support Cadence users and technologists interacting to exchange ideas, news, technical information, and best practices to solve problems and get the most from Cadence technology. The community is open to everyone, and to provide the most value, we require participants to follow our Community Guidelines that facilitate a quality exchange of ideas and information. By accessing, contributing, using or downloading any materials from the site, you agree to be bound by the full Community Guidelines.