[Pw_forum] parallel computation too slow

[Elie M]

Dear all,
I am running phonon calculations for a supercell of 60 atoms at the gamma point. I am running the calculation at the gamma point only. First I tried running it on two nodes but then I realised it is going too slow  (I have got  180 IRRs representations). I then changed to 3 nodes but still , things are slow. The threshold tr2_ph was set to 10^(-17) as higher values produced negative (frequency)^2 modes. What could the possible causes of this slowness be? Is it something to do with the nodes or with phonon calculations in general? Is there a way to check?

Regards
Elie MUniversity of NottsNG7 2RDUK 		 	   		  
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