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mplacke
Posts: 2
Registered: ‎03-14-2013

performance slowdown after ~50 iterations

138 Views, 3 Replies
03-14-2013 02:51 PM

I am doing a run with 3M+ fluid elements, and when I launch the analysis, I get the notification that the first 25 iterations run in just a few hours. Then the next 25 take about a day, and then it takes almost a day to run just a couple iterations. So I stopped the run, and re-started it just to see what would happen. It did almost the exact same thing- The first 25 runs of the same model after the restart took several hours, the second 25 took a bit longer, and now it is crawling.

 

I have not seen this before on large runs. They tend to solve at a fairly uniform rate (or crash and burn somewhere along the way).

 

Any words on if this is normal or has a known cause?

 

BTW- The analysis is being run remote on a dedicated  1-socket, 4-core, 2.8GHz machine with 12GB memory running 64-bit Windows 7 OS.

 

Thanks for any comments.

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Product Support
wildej
Posts: 961
Registered: ‎08-25-2011

Re: performance slowdown after ~50 iterations

03-15-2013 04:16 AM in reply to: mplacke

Hi,

 

The only cause I can think of is that you are running transient and filling the HDD up?

If not, feel free to share the support file (cfz) so we can take a look here.



Jon Wilde
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New Member
mplacke
Posts: 2
Registered: ‎03-14-2013

Re: performance slowdown after ~50 iterations

03-15-2013 07:12 AM in reply to: wildej
Thank you for the suggestion with regard to disk space. I just double checked, and there are 259GB free out of 463GB on my hard drive. You never know, but that seems like plenty of headroom. Mike Placke Convey Computer (214) 576-9691 mplacke@conveycomputer.com
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Product Support
wildej
Posts: 961
Registered: ‎08-25-2011

Re: performance slowdown after ~50 iterations

03-15-2013 07:24 AM in reply to: mplacke

Should be plenty! Feel free to share the cfz and we can take a look.



Jon Wilde
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