Hi Adrian,

Thanks for the info.

We are currently considering scaling up some of our lumped element models, so the performance issue will probably become a blocker for us.

Hi perost,

I've tried it on r10484 this morning and it's working now. Thanks for fixing it so quickly!

I've noticed that omc doesn't scale well on this model and others. Here are the times taken to run the above model with different values of N:

N    Time (s)
16    6
32    11
64    37
128    302
256    4079

Do you know how to improve omc performance on large problems?

Hi All,

I've been trying to do a very simple model of a transmission line, see below.

model circuit

  Modelica.Electrical.Analog.Sources.SineVoltage V (V = 15, freqHz = 795.8);

  Modelica.Electrical.Analog.Lines.OLine 

    T (length = 100.0, r = 4, l = 3e-3, g = 1e-6, c = 0.015e-6, N = 4);

  Modelica.Electrical.Analog.Basic.Ground ground;

equation

  connect (ground.p, V.n);

  connect (V.p, T.p1);

  connect (T.p3, ground.p);

end circuit;

When I increase N to a number greater than 13, omc (1.8.0, r10397) fails and gives the following error:
returning NULL (not enough memory) from rml_major_collection!
returning NULL (not enough memory) from rml_older_alloc!
rml_prim_gcalloc failed to get 805306368 words
returning NULL (not enough memory) from rml_prim_gcalloc!
Segmentation fault

It also gobbles up all 16GB of memory before crashing. Has anyone seen a similar error before?