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NX-NASTRAN Matrix Reduction Time

Hello,

 

I'm wondering where I can find the wall time (end_time - start_time) taken to reduce the stiffness matrix? F04? F06? LOG? I'm running a linear analysis with contact iterations.

 

Thanks!

6 REPLIES

Re: NX-NASTRAN Matrix Reduction Time

Maybe this?

2017-02-28_21-00-53.png

Re: NX-NASTRAN Matrix Reduction Time

Thanks, but that entry doesn't exist for linear analyses.

Re: NX-NASTRAN Matrix Reduction Time

Performance statistics for Nastran are in the f04 file. If you are interested in decomp, then look for the following in your f04 file:

 

15:18:31 0:00 502.0 0.0 0.2 0.0 SEKRRS 168 DCMP BEGN
*** USER INFORMATION MESSAGE 4157 (DFMSYN)
PARAMETERS FOR SPARSE DECOMPOSITION OF DATA BLOCK KLL ( TYPE=RSP ) FOLLOW
MATRIX SIZE = 7698 ROWS NUMBER OF NONZEROES = 73033 TERMS
NUMBER OF ZERO COLUMNS = 0 NUMBER OF ZERO DIAGONAL TERMS = 0
User information:
When spill is indicated, the model is too large to fit into memory.
The job may run faster by increasing the available memory (this will
decrease the number of spill groups).
See the NX NASTRAN Installation and Operation Instructions for a
description of these terms. See also the NX NASTRAN Numerical
Methods User's Guide.
CPU TIME ESTIMATE = 0 SEC I/O TIME ESTIMATE = 0 SEC
MINIMUM MEMORY REQUIREMENT = 1952 KB MEMORY AVAILABLE = 9030288 KB
MEMORY REQR'D TO AVOID SPILL = 2984 KB MEMORY USED BY MMD = 424 KB
EST. INTEGER WORDS IN FACTOR = 257 K WORDS EST. NONZERO TERMS = 539 K TERMS
ESTIMATED MAXIMUM FRONT SIZE = 297 TERMS RANK OF UPDATE = 128
*** USER INFORMATION MESSAGE 6439 (DFMSA)
ACTUAL MEMORY AND DISK SPACE REQUIREMENTS FOR SPARSE SYM. DECOMPOSITION
User information:
This message is issued in the .F04 file after decomposition.
It tells how much memory and desk space were actually required.
SPARSE DECOMP MEMORY USED = 2984 KB MAXIMUM FRONT SIZE = 297 TERMS
INTEGER WORDS IN FACTOR = 38 K WORDS NONZERO TERMS IN FACTOR = 539 K TERMS
SPARSE DECOMP SUGGESTED MEMORY = 2984 KB
*8** Module DMAP Matrix Cols Rows F T IBlks NBlks NumFrt FrtMax
DCMP 168 LLL 7698 7698 13 1 2 17 1095 297 *8**
*8** Module DMAP Matrix Cols Rows F T NzWds Density BlockT StrL NbrStr BndAvg BndMax NulCol
DCMP 168 SCR 301 1 7698 2 1 7698 1.00000E+00 3 7698 1 7698 7698 0 *8**
DCMP 168 SCR 302 1 7698 2 1 7698 1.00000E+00 3 7698 1 7698 7698 0 *8**
15:18:32 0:01 502.0 0.0 0.2 0.0 SEKRRS 168 DCMP END

Re: NX-NASTRAN Matrix Reduction Time

So then I guess the time would be 15:18:31 0:00 - 15:18:32 0:01, but I'm not so sure about the time format, especially the 0:00 and 0:01. Maybe the 0:01 is the elapsed time.

Solution
Solution
Accepted by topic author Kava
3 weeks ago

Re: NX-NASTRAN Matrix Reduction Time

The top of the f04 file has the heading information, see the screenshot below. Sorry the coulumns of the f04 got scrambled in my first reply. Also see the NX Nastran Users Guide, Section 4.3 "Understanding the f04 File" for help in understanding, there is a lot of valuable performance information in the f04. You can add even more detail by setting Diag 8,15 and 56. With those Diag's, you will see every line of the solution sequence that gets executed.

 

2017-03-01 10_22_17-TextPad .f04.png

 

 

 

Re: NX-NASTRAN Matrix Reduction Time

[ Edited ]

I think I've found it with your help. There is no DCMP duration listed, but the timestamps can be used to calculate it by searching for the lines "DCMP    BEGN" and then "DCMP    END":


 Day_Time  Elapsed     I/O_Mb      Del_Mb     CPU_Sec    Del_CPU    SubDMAP Line (S)SubDMAP/Module

...

 16:51:24     0:17      273.0         0.0        19.8        0.3    PHASE1D 394     DCMP    BEGN 

...
 16:51:37     0:30      850.0       577.0        76.0       56.1    PHASE1D 394     DCMP    END