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[Simone Del Nero]

Hello, everyone,

I am conducting a design optimization in Ansys APDL using a code I wrote. 
In many cases I am able to obtain an optimised solution, while in others the simulation was terminated prematurely and I got the following error (file error):

" An unexpected error ( Segmentation Violation ) has occurred...  ANSYS   
 internal data has been corrupted.  ANSYS is unable to recover and will  
 terminate.  Previously saved files are unaffected.  Please send the     
 data leading to this operation to your technical support provider, as   
 this will allow ANSYS, Inc to improve the program."

I understand from the error obtained that it is a memory problem. 
What could be the possible solutions? 

[Aniket]

The error you're encountering, known as a Segmentation Violation, is indeed often related to memory issues. It can occur when the program tries to access a memory location that it's not allowed to, which can be due to various reasons. Here are some possible solutions:

1. **Balancing CPU, Memory, and I/O**: To achieve good overall performance, it's crucial to have the correct balance of processors, memory, and disk I/O. The CPU speed is an obvious factor of performance. However, the other two factors—memory and disk I/O—are not always so obvious. Large amounts of memory can not only extend the model size that can be simulated on a given machine but also play a significant role in achieving optimal performance https://ansyshelp.ansys.com/Views/Secured/corp/v232/en/ans_per/percpumemio.html

2. For desktop systems and many cluster configurations, it's important to understand that many cores share the same disk resources. Therefore, obtaining fast I/O performance in applications such as Mechanical APDL is often not as simple as adding a fast RAID0 configuration. Performance is best when solver I/O can be eliminated or when multiple nodes are used for parallel runs, each with a separate local I/O resource: https://ansyshelp.ansys.com/Views/Secured/corp/v232/en/ans_per/perioansys.html

3. If Mechanical APDL simulations can run with all file I/O cached by a large amount of physical memory, then disk resources can be concentrated on storage more than performance. A good rule of thumb is to have 10 times more disk space than physical memory available for your simulation

4. If all fails, and memory upgrade is not possible, you can try to reduce your model size

-Aniket

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