Got Stuck in Harmonic Balance Analysis

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