1 Topic by morad (edited by morad 12-07-2010 17:27:50)

  • From: Imperial College London
  • Registered: 19-02-2009
  • Posts: 28

Topic: Selective context file output

Dear Borek,

It has recently come to my attention that when one runs a simulation using the "-c" option it will create a context file for every single increment and the user does not have any control.
This might not be a big problem in implicit cases, but when it comes to dynamic nonlinear explicit simulations, it make a big difference. Writing to an ASCII file in every step takes both time and disk space. It quadrupled the time needed for one of my simulations and had to wait for 12 hours instead of 3.5 and also had to manage 250GB worth of context files.

It might be worth adding a feature similar to those found in the output manager and vtk export module to ask for an output every n increments rather than how it is now.

Kind regards
Morad

morad's Website

2 Reply by bp

  • bp
  • Administrator
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  • From: Prague, Czech Rep.
  • Registered: 02-03-2007
  • Posts: 1,047

Re: Selective context file output

Dear Morad,

you can use "contextoutputstep" keyword in analysis record, followed by a number, which forces the context file to be created only every n-th solution step. So, for example:

DIIDynamic nsteps 100 deltaT 0.1 alpha 0.0 beta 0.0 Psi 1.0 contextoutputstep 10

will force the context fuile to be created for every 10-th step.

When contextoutputstep is used, you should not use "-c" option on the command line, as it will override the contextoutputstep setting.
The same effect, as using "-c" can be achieved by using "contextoutputstep 1" in the input file.

Borek.

bp's Website