[Wien] machines file and klist splitting
Fred Nastos
nastos at physics.utoronto.ca
Fri Oct 15 23:35:42 CEST 2004
I setup a .machines file, and I'm suspicious of the how the klist is being
split. It seems non-optimal, so I suspect I did something wrong.
The machine has two dual cpu slave nodes, and one masternode.
Actually, the machine has many nodes, but let's assume I am using
only using two nodes.
The .machines file I made is:
## begin .machines file ##
granularity:1
1:node001:1
1:node001:1
1:node002:1
1:node002:1
## end .machines file ##
I have 42 kpoints. testpara_lapw tells me that it will split the list into 5
smaller lists. Four lists have 10 points, and one list has 2 points. The
output from testpara_lapw is:
### begin testpara output ###
Granularity set to 1
Extrafine unset
klist: 42
machines: node001 node001 node002 node002
procs: 4
weigh(old): 1 1 1 1
sumw: 4
granularity: 1
weigh(new): 10 10 10 10
Distribution of k-point (under ideal conditions) will be:
1 : node001(10) 10k
2 : node001(10) 10k
3 : node002(10) 10k
4 : node002(10) 10k
5 : node001(10) 2k
### end testpara output ###
Indeed when I run the calculation, it seems to send 10 kpoints to each cpu,
and then 2 kpoints to node01.
Would it not make more sense to have the list split into 4 sublists, and
send 11 points to two cpus and 10 points? That is, it seems like a
distribution of:
1: node001(10) 11k
2: node001(10) 11k
3: node002(10) 10k
4: node002(10) 10k
would be more optimal. No?
Thanks
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