Description: How to maximize RAM usage to reduce scratch size in Optistruct.
Product/Topic Name : Optistruct 2026.
** Altair OptiStruct(TM) 2026 **
** Advanced Engineering Analysis, Design and **
** Optimization Software from Altair Engineering, Inc. **
** OptiStruct includes an enhanced proprietary version of NASTRAN **
** Windows 10 (Build 9200) ————— **
** 16 CPU: 11th Gen Intel(R) Core(TM) i7-11850H @ 2 .50GHz **
** 115531 MB RAM, 158383 MB swap **
** Build: 1291590uwn33xxx_Ce64RB6s8UH14M-000 1046004004000020004204 **
I HAVE 128 Gb RAM IN MY COMPUTER.
In this simulation I get the following information:
MEMORY ESTIMATION INFORMATION :
Solver Type is: Sparse-Matrix Solver
Direct Method
Static Memory (RAM) Allocated in Preprocessor : 9748 MB
MUMPS Solver will Run Out-Of-Core with Estimated Memory : 46473 MB
Estimated Total Memory (RAM) : 56221 MB
Estimated Memory (RAM) for Out-of-Core Solution : 54997 MB
Estimated Memory (RAM) for In-Core Solution : 157535 MB
(Note: The Minimum Memory Requirement is limited by Assembly Module.)
DISK SPACE ESTIMATION INFORMATION :
Estimated Disk Space for Output Data Files : 2802 MB
Estimated Scratch Disk Space for In-Core Solution : 9476 MB
Estimated Scratch Disk Space for Out-of-Core Solution : 106048 MB
As I don't have 157535 MB, Optistruct executes de Out-of-Core Solution with 106048 MB scratch.
The question would be:Is there any configuration possible to reduce the scratch size and increase the RAM used in the Out-of-Core Solution?I read that maybe MUMPS doesn't permit this maximization and that I should move to PARDISO solver.It is really disappointing having 128 Gb available and not using half of it.
