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<DIV><SPAN class=850172400-03112006><FONT size=2>Dear WRF
users,</FONT></SPAN></DIV>
<DIV><SPAN class=850172400-03112006><FONT size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=850172400-03112006><FONT size=2>I have an original question: I
use ARW WRF compiled with option 4 for IBM computer (OBJECT_MODE =
64).</FONT></SPAN></DIV>
<DIV><SPAN class=850172400-03112006><FONT size=2>I ran the
same test case on 1 node (16 processors) and on 2 nodes (32
processors). The results were stunning for me: 1 hour on 1 node (16
prosc) runs 2.30 minutes and 1 hour on 2 nodes (32 procs) runs 10
minutes!!! </FONT></SPAN><SPAN class=850172400-03112006><FONT size=2>So
far for ARW WRF (option 4, IBM) in my case 1 node 4 times faster than 2
nodes!?</FONT></SPAN></DIV>
<DIV><SPAN class=850172400-03112006><FONT size=2>My system operator tries
to argue that this is a fault of ARW WRF model:something like 'that
a split of a quite small domain (XMAX = YMAX = 34, 4 grids) for 2
nodes destroys all advantages of using 32 processors and makes the things
even worse (brakes a speed of WRF run).</FONT></SPAN></DIV>
<DIV><SPAN class=850172400-03112006><FONT size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=850172400-03112006><FONT size=2>Does anybody have any
experience about such kind of 'reverse' events?</FONT></SPAN></DIV>
<DIV><SPAN class=850172400-03112006><FONT size=2>Is the guess of my system
administrator is right or is there something wrong with IBM
initial configuration? </FONT></SPAN></DIV>
<DIV><SPAN class=850172400-03112006><FONT size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=850172400-03112006><FONT size=2>Any help is very highly
appreciable.</FONT></SPAN></DIV>
<DIV><SPAN class=850172400-03112006><FONT size=2>Many
thanks,</FONT></SPAN></DIV>
<DIV><SPAN
class=850172400-03112006><!-- Converted from text/plain format --><BR>
<P><FONT size=2>^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^<BR>Mikhail
Titov<BR>Doctoral Candidate<BR>Department of Geography<BR>University of
Canterbury - Te Whare Wananga o Waitaha<BR>Private Bag
4800<BR>Christchurch<BR>New Zealand<BR>Telephone: +64 3 364 2987 ext
8839<BR>Fax (Department): +64 3 364
2907<BR>^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^</FONT>
</P> </SPAN></DIV>
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