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kb:parallel [2018/02/14 07:48] – [Basic Questions] enviadminkb:parallel [2021/04/21 09:38] (current) – [Practical Issues] enviadmin
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 Many people have a concept what parallel computing is, and they want to have it in their applications, but as this is a relatively new area of computing, it contains many misunderstandings and misleading expectations we try to clarify in this Knowledge Base. Many people have a concept what parallel computing is, and they want to have it in their applications, but as this is a relatively new area of computing, it contains many misunderstandings and misleading expectations we try to clarify in this Knowledge Base.
  
-====== Changed Pressure Solver  ====== 
-With the introduction of Parallel Computing, it was neccessary to rewrite the pressure-solver used to obtain the wind field. 
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-However, it can be noted, that the new parallel solver produces slightly different results compared to the old, sequential solver. 
-If you want to keep the old solver for compatibility reasons, please add the following lines in your .SIM files: 
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-<WRAP center round box 60%> 
-[SORMODE] 
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-SOR solver (0: classic, 1:parallel)= 0 
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-</WRAP> 
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-This will be more clearer in the next release of ENVI-met. 
  
 ====== Q&A on Parallel Computing with ENVI-met  ====== ====== Q&A on Parallel Computing with ENVI-met  ======
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 ??? I started an ENVI-met without any specific CPU usage instructions. How many CPUs cores will it use? ??? I started an ENVI-met without any specific CPU usage instructions. How many CPUs cores will it use?
  
-The default setting is to use all available CPU cores.+The default setting is to use all available CPU cores, that are assigned by the operating system. How many cores this will actually be in the end, will not only depend on your computer, but also on the amount of other applications running parallel to ENVI-met. Also, the amount of cores is assigned dynamically by WINDOWS and is also requested dynamically by ENVI-met depending on the specific simulation task. In other words: If ENVI-met is operating in a model section that is not parallel, it will not request more than one core.