Summary Information

OptiStruct always creates an .out file which contains summary information for the job.

This information can be echoed to the screen through the inclusion of the SCREEN I/O Options Entry in the input data or through the use of the -out command line option (Run Options for OptiStruct).

This file also contains memory and disk space estimates. The disk space estimates for eigenvalue analyses (normal modes, linear buckling, modal methods of frequency, transient response, and fluid-structure coupling (acoustics)) are sometimes very conservative and can be three times as much as is truly used. This is because it is not fully predictable how much data needs to be saved to scratch files.

The true usage of memory and disk space is reported at the bottom of the file after the solver has finished.

Should the job be re-run in the same location, the .out file is not overwritten, but is instead moved to _#.out, where # is the lowest available three digit number that creates a unique file name.

For example, if filename.fem were run in a directory already containing filename.out, the existing filename.out would be moved to filename_001.out, and the summary information for the new job would be written to filename.out. Should the job be repeated again, the existing filename.out would be moved to filename_002.out, and the summary information for the latest job would be written to filename.out.

The filename.out is the only file that is saved in this manner. All other results files will be overwritten.

Recommendations

  1. Try running OptiStruct with the default setting first (without specification of the -len or -core options).
  2. Do a check run before submitting large jobs (>500,000 dof) to NQS to make sure sufficient NQS memory is being provided. The -lM option can be used to change the NQS memory. Be sure to include at least 12Mb for the executable in addition to the memory necessary to solve the problem. A check run can also assist in debugging input data without having to wait in a queue.