Thunderhead Engineering Forum

Please login or register.

Login with username, password and session length
Advanced search  

News:

Forum moved to https://forum.thunderheadeng.com

Author Topic: PC Configuration For Fire dynamics simulation  (Read 3932 times)

prasanraj2805

  • Member
  • **
  • Posts: 15
    • View Profile
PC Configuration For Fire dynamics simulation
« on: November 27, 2015, 09:21:32 pm »

Hi

I am using Pyrosim software for simulating some paint booth..
But my simulation is running for more than five days just for 150sec
kindly suggest what is the better configuration in PC For quick result of simulation

Note:  I cannot reduce mesh size because i am afraid if it affects my results

please suggest your ideas ,, thank you
Logged

mdangelmaier

  • Member
  • **
  • Posts: 50
    • View Profile
Re: PC Configuration For Fire dynamics simulation
« Reply #1 on: November 30, 2015, 01:47:42 am »

Please attach your .psm file, otherwise it is kind of hard to tell what could be wrong with the model
Logged

Eagle

  • Member
  • **
  • Posts: 16
    • View Profile
Re: PC Configuration For Fire dynamics simulation
« Reply #2 on: November 30, 2015, 10:21:24 am »

Hi Prasanraj,

how many CPU threads have your computer?
Each mesh can be processed by one CPU thread. If you have 8 threads , then you can calculate 8 meshes at the same time. If you have only one mesh with a small cell density, so it works only one thread on your mesh. It could be an answer, if you split up your mesh into more meshes. You can see how much threads you have by looking task manager --> see my Attachment (8 Threads)

best regards,
Eagle
Logged

Feyd

  • Member
  • **
  • Posts: 11
    • View Profile
Re: PC Configuration For Fire dynamics simulation
« Reply #3 on: December 02, 2015, 02:46:30 am »

Hello Prasanraj,

I tried a lot of configuration for FDS, and there are my feedbacks :
     - The number of CPU and CPU threads doesn't accelerate the calculation. In fact, the FDS engine doesn't use parallel calculation. So it doesn't accelerate the calculation, but permit to calculate a bigger number of cells.
     - The ram quantity don't accelerate the calculation, but allows more cells too.
     - The real factor to accelerate calculation is CPU velocity : a 4Ghz CPu will calculate faster than a 2Ghz.

I have for now a Xeon CPU @3.7Ghz and I can do a calculation for 5million cells in 2/5 days (1800sec simulation), depending of the complexity of the model. keep in mind that the number of output you needs modify the calculation time.

hope my answers will help you.

BR
« Last Edit: December 02, 2015, 02:53:58 am by Feyd »
Logged

Charlie Thornton

  • Thunderhead
  • *****
  • Posts: 851
    • View Profile
Re: PC Configuration For Fire dynamics simulation
« Reply #4 on: December 09, 2015, 11:12:57 am »

My experience differs from Feyd's. I have see significant improvements in performance using MPI-based multi-mesh parallelism. My approach to get the fastest simulations is to divide the simulation into N meshes with approximately equal numbers of cells - where N is the number of physical cores available on the machine. If hyper threading is enabled, my experience is that is is slightly better to use half the number of "logical" cores available on the machine but different people have had different experiences.

I also set the OMP_NUM_THREADS variable to "1" because I want all the cores/threads busy with MPI-based parallelism and no effort divided into OpenMP-based parallelism because only about 60% of the code in the main loop is parallelizable via OpenMP (i.e. I've gotten more benefit by committing fully to MPI and avoiding OpenMP when possible).

You can identify the number of cores vs logical processors available on your machine using the following console command:

WMIC CPU Get DeviceID,NumberOfCores,NumberOfLogicalProcessors
Logged

TomSands

  • New Member
  • *
  • Posts: 1
    • View Profile
Re: PC Configuration For Fire dynamics simulation
« Reply #5 on: July 09, 2020, 03:09:46 pm »

You guys might not believe it, but what helped me was optimizing my PC. My friend was telling me to do it, but at first I was thinking that it made no sense doing it. My PC was slow and I had problems with everything so I decided to give it a shot. He told me to go on https://thinkmobiles.com/blog/best-pc-optimization-software and choose one. I went for the cheapest one and I was amazed with the results. My PC was much faster and it stopped crashing. It was really worth it because I was already planning to buy a new one, but while this one is working I am keeping it.
« Last Edit: July 16, 2020, 08:23:27 am by TomSands »
Logged