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<font size="+1"><font face="Courier New, Courier, monospace">Dear
Preeti,<br>
<br>
RSL_LITE does not support dynamic load balancing. Years
ago, a version of MM5 called MM90 was developed and tested that
included an experimental version of dynamic load balancing. See:
<a class="moz-txt-link-freetext" href="ftp://info.mcs.anl.gov/pub/tech_reports/reports/P659.ps.Z">ftp://info.mcs.anl.gov/pub/tech_reports/reports/P659.ps.Z</a><br>
<br>
The
approach and results, while interesting from a computer science
research point of view, were never sufficiently compelling to justify
the cost and difficulty of developing and maintaining this capability
for the distributed-memory parallel MM5 or the WRF model which followed
it. In addition, the old RSL code had some
unacceptable limits on domain size and scalability to large numbers of
processors. Therefore, RSL was replaced by the much simpler but more
scalable RSL_LITE parallel layer that is distributed with WRF today.
Physics load imbalance remains a nuisance. Please feel free to contact
me if you have any questions.<br>
<br>
-John</font></font><br>
<br>
Preeti wrote:
<blockquote
cite="mid:e6c04ea30911091015q5c930ec4k5bfd4ae028fd82ca@mail.gmail.com"
type="cite">
<pre wrap="">Hi
I have a question related to dynamic load balancing in WRF. I am using
WRFv3.0.1. The documentation of WRFv3
<a class="moz-txt-link-freetext" href="http://www.mmm.ucar.edu/wrf/users/wrfv3/updates.html">http://www.mmm.ucar.edu/wrf/users/wrfv3/updates.html</a> mentions the
following -
* Full RSL_LITE support for nesting, transposes, periodic BC’s, etc.
RSL communication package has been retired in V3
However I have read the paper by John G. Michalakes "RSL: A Parallel
Runtime System Library for Regional Atmospheric Models with Nesting"
which talks about Dynamic Load Balancing in RSL by re-mapping. I could
not find any RSL_LITE documentation which talks about re-mapping to
new processors due to load imbalance.
Since RSL_LITE replaces RSL in WRF, I wanted to know if there is any
similar feature implemented in RSL_LITE in WRF for dynamic load
balancing?
Appreciate your help very much.
Thanks
Preeti
_______________________________________________
Wrf-users mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Wrf-users@ucar.edu">Wrf-users@ucar.edu</a>
<a class="moz-txt-link-freetext" href="http://mailman.ucar.edu/mailman/listinfo/wrf-users">http://mailman.ucar.edu/mailman/listinfo/wrf-users</a>
</pre>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
-----------------------------------------------------------
John Michalakes, Software Engineer <a class="moz-txt-link-abbreviated" href="mailto:michalak@ucar.edu">michalak@ucar.edu</a>
NCAR, MMM Division voice: +1 303 497 8199
3450 Mitchell Lane fax: +1 303 497 8181
Boulder, Colorado 80301 U.S.A. cell: +1 720 209 2320
<a class="moz-txt-link-freetext" href="http://www.mmm.ucar.edu/individual/michalakes">http://www.mmm.ucar.edu/individual/michalakes</a>
-----------------------------------------------------------
</pre>
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