Re: PROBLEM IN THE BOUNDARY CONDITIONS USING COMPRESSABLE MODEL
Posted: Wed Apr 21, 2021 7:51 am
Hi Yvan,
a good example is the laptop I used to test the calculation with CS 5.0.4. The specs were:
CPU: Intel Core i5-4210U (Dualcore at 1.70 Ghz)
Ram: 8 Gb DDR3
I ran a calculation with 250.000 time steps, a step size of 5e-7 s (variable), CFL <= 0.4. It took a week to finish. This laptop is totally unusable. However, there were no hurry because I was busy in other projects.
Now we set up a desktop PC using Ubuntu 20.04 and CS 7.1. The specs now are:
CPU: AMD Ryzen 9 3950X 16-Core Processor
RAM: 64 Gb DDR4 3200 Mhz
I ran the same calculation for comparison with only one difference. There were only 150.000 time steps. I started yesterday after lunch and expected the calculation to be finished this morning. Somehow strange to me appears the listings file. The time steps listed starts at 1, 2, 3 and so on until 10. Then it jumps to 100! After more than 12 hours running it seems that CS did only 100 steps of 150.000. All CPUs are on 100%. This would be even slower than with my crappy laptop.
Do you have any suggestions? Do I have to edit something in the performance settings? Till now I left everything default.
Kind regards,
Christopher
a good example is the laptop I used to test the calculation with CS 5.0.4. The specs were:
CPU: Intel Core i5-4210U (Dualcore at 1.70 Ghz)
Ram: 8 Gb DDR3
I ran a calculation with 250.000 time steps, a step size of 5e-7 s (variable), CFL <= 0.4. It took a week to finish. This laptop is totally unusable. However, there were no hurry because I was busy in other projects.
Now we set up a desktop PC using Ubuntu 20.04 and CS 7.1. The specs now are:
CPU: AMD Ryzen 9 3950X 16-Core Processor
RAM: 64 Gb DDR4 3200 Mhz
I ran the same calculation for comparison with only one difference. There were only 150.000 time steps. I started yesterday after lunch and expected the calculation to be finished this morning. Somehow strange to me appears the listings file. The time steps listed starts at 1, 2, 3 and so on until 10. Then it jumps to 100! After more than 12 hours running it seems that CS did only 100 steps of 150.000. All CPUs are on 100%. This would be even slower than with my crappy laptop.
Do you have any suggestions? Do I have to edit something in the performance settings? Till now I left everything default.
Kind regards,
Christopher