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Caleb Saunders

Optimisation still running, CPU usage 0%

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Hi all,

I have been running an optimisation on a mountain bike frame with multiple load cases. A few times (not necessarily the frame model) when running optimisation with a small element size for multiple load cases,  I have encountered an issue with the program. The Memory (ram) is fully utilised, almost 100% from the processes running, though the processes are not being processed by the CPU, this is causing hard faults to occur. I have left an optimisation run for 17.5 hours, only to not be completed (I know this task may take longer), I terminated due to nothing being processed. This fault may be arising from terminating other runs if they start in parallel. I have attached pictures of my resource monitor for the issue and a good run. In a normal run the CPU fluctuates from around 13 to 100% averaging 40% on some processes.

Computer Specs:

CPU: Intel I7 3610QM  2.3Ghz w turbo

Memory:  8Gb DDR3

Graphics: 2Gb NVidia GT630M

OS: Windows 7 x64 Home Prem.

CPU.PNG

Ram.PNG

CPU good.PNG

Ram good.PNG

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Hi Caleb,

 

I guess you are runing "out of core" with your optimization:

image.png

You can easily check if you are running "in core" or "out of core", by taking a look at the topoOpt.out file, which is located in your scratch directory (by default in the user directory).

image.png

Inside you will find information regarding the recent Iteration (easy to see if your computation is still runing). Furthermore the info regarding your Memory usage:

image.png

Within the Iteration 0 you will get the infomation if it is running "in core" or not:

image.png

In case it isn't running incore, you might decrease the amount of elements by increasing the "Minimum Thickness constraint" inside the "Run Optimization" window:

image.png

 

Out of Core Simulations are working usually, but they are way slower as the RAM isn't large enouth to fit the computation. Instead, data is shifted between your HDD, RAM and the Processor. As a result 90% of the time, no computation is going on - but data is read and written to your HDD.

 

You might also should think about upgrading your RAM - 8GB RAM is really not much for optimizations. To put things into perspective: I'm working with 32GB of RAM.

Highend Customers, usuallly got 128GB and even more.

 

 

Regards,

Felix

 

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Thank you a lot Felix that explains a lot about how it runs. I knew this computer wouldn't be up to spec, though I have to use what I have as it's for university thesis. I completed two optimisations overnight at 15mm min. with a third at 10.33 (as initially input by inspire) still running  at the moment and have checked that it is "in-core", it is still doing the same thing but seems to be slowly progressing through an iteration every few hours (up to 6 now). It sits around 0 percent CPU and every hour or so starts up again as normal. There is still one gb of ram free most of the time , is this still expected behaviour? Or should I manually input the amount of ram allocated? I will try to upgrade my ram to 16 gb if possible. Is it possible to put the hard-drive in an alternate computer and run inspire, or is the licence linked to the network hardware too? 

I have some questions to try and improve run time. Is it possible to manually input the mesh characteristics for optimisation (refine mesh in critical areas)? Does removing parts of design space that is not used in any load cases or most element thicknesses greatly improve time (less mesh and analysis?)?

Thank you again for your help,

Caleb Saunders

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Hi Caleb,

 

Glad to hear this was helpful! If you are changing your PC, you have to request another license through our website:

https://solidthinking.com/Buy.aspx?category=Buy&item=Students Educators

You can do mesh refinement with 2018.1, but it will not be helpful for the optimization - but the analysis:

Click on this tiny triangle next to "Setup":

image.png

Then choose "Mesh Control":

image.png

 

You can use it to increase or decrease the elementsize by selecting surfaces of your model. But again - this isn't helpful for an optimization.

 

Regards,

Felix

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