dmpoption

Mapdl.dmpoption(filetype='', combine='', **kwargs)

Specifies distributed memory parallel (Distributed ANSYS) file

APDL Command: DMPOPTION combination options.

Parameters:

filetype

Type of solution file to combine after a distributed memory parallel solution. There is no default; if (blank), the command is ignored.

RST - Results files (.RST, .RTH, .RMG, .RSTP)

EMAT - Element matrix files (.EMAT).

ESAV - Element saved data files (.ESAVE)

MODE - Modal results files (.MODE)

MLV - Modal load vector file (.MLV)

IST - Initial state file (.IST)

FULL - Full matrix file (.FULL)

RFRQ - Reduced complex displacement file (.RFRQ)

RDSP - Reduced displacement file (.RDSP)

combine

Option to combine solution files.

Yes - Combine solution files (default).

No - Do not combine solution files.

Notes

The DMPOPTION command controls how solution files are written during a distributed memory parallel (Distributed ANSYS) solution. This command is most useful for controlling how results files (.RST,.RTH, etc.) are written.

In a distributed memory parallel solution, a local results file is written by each process (JobnameN.ext, where N is the process number). By default, the program automatically combines the local results files (for example, JobnameN.RST) upon leaving the SOLUTION processor (for example, upon the FINISH command) into a single global results file (Jobname.RST) which can be used in ANSYS postprocessing. To reduce the amount of communication and I/O performed by this operation, you can issue the command DMPOPTION,RST,NO to bypass this step of combining the local results files; the local files will remain on the local disks in the current working directory. You can then use the RESCOMBINE command macro in the POST1 general postprocessor (/POST1) to read all results into the database for postprocessing.

The RESCOMBINE command macro is intended for use with POST1. If you want to postprocess distributed parallel solution results using the POST26 time-history postprocessor (/POST26), it is recommended that you combine your local results files into one global results file (DMPOPTION,RST,YES or COMBINE).

Local .EMAT, .ESAV, .MODE, .MLV, .IST, .RFRQ, .RDSP, and .FULL files are also written (when applicable) by each process in a distributed memory parallel solution. If these files are not needed for a downstream solution or operation, you can issue the command DMPOPTION,FileType,NO for each file type to bypass the file combination step and thereby improve performance. You should not bypass the file combination step if a downstream PSD analysis or modal expansion pass will be performed.

If DMPOPTION,MODE,NO or DMPOPTION,RST,NO is specified in a modal analysis, element results cannot be written to the combined mode file (Jobname.MODE). In this case, if Distributed ANSYS is used in a downstream harmonic or transient analysis that uses the mode- superposition method, the MSUPkey on the MXPAND command can retain its value. However, if shared memory parallel processing is used in the downstream harmonic or transient analysis, the MSUPkey is effectively set to NO.

The DMPOPTION command can be changed between load steps; however, doing so will not affect which set of solution files are combined. Only the last values of FileType and Combine upon leaving the solution processor will be used to determine whether the solution files are combined. For example, given a two load step solution and FileType = RST, setting Combine = NO for the first load step and YES for the second load step will cause all sets on the local results files to be combined. If the opposite is true (Combine = YES for the first load step and NO for the second load step), no results will be combined.

After using DMPOPTION to suppress file combination, you may find it necessary to combine the local files for a specific FileType for use in a subsequent analysis. In this case, use the COMBINE command to combine local solution files into a single, global file.