[Wien] parallel lapw2 slow

[Atta-fynn, Raymond]

Dear Wien Users,
 
I'm running WIEn2k on a 16 node beowulf cluster with two CPUs per node. 
When I run several parallel jobs (about 3 or 4 jobs at a time using 
4 nodes per job), lapw1 scales almost linearly in parallel 
but parallel lapw2 ( and sometimes lapwso) is way slower, compared to  
single node. For example, lapw2 takes about 45 seconds on 
a singe node but for 4 nodes it can take as long as 15 minutes. 
I find this quite confusing.
I've run several cases and this fact is 
consistently true. Is there any way that I can constrain lapw2 
to run in serial mode whiles lapw1 runs in parallel?
 
Thanks
 
R. Atta-Fynn
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