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hi all,<br>
<br>
we have just pushed an update to the Manhattan release of DART<br>
which fixes a performance problem if all of these were true:<br>
<br>
1) your model_mod does vertical coordinate conversion of<br>
either observations or state for localization; and <br>
2) if you were trying to use &assim_tools_nml :: distribute_mean
= .true. <br>
to save memory on each task; and <br>
3) you were running with a large task count.<br>
<br>
if you had tried this option before and it was too slow it might<br>
be worth timing it again. note that this bug did not change the<br>
results, only the amount of time the code took to run.<br>
<br>
along with setting 'distribute_mean = .true', we recommend<br>
using the default of 'convert_all_obs_verticals_first = .true.'<br>
in that same namelist.<br>
<br>
whether you also set 'convert_all_state_verticals_first = .true.'<br>
depends on whether you expect most or all of your model state<br>
to be modified by the assimilation or not. if only a small part of<br>
your state is impacted by observations, the default value of .false.<br>
for the state may be faster for you. if most of your state is going<br>
to be close enough to at least one observation to be impacted<br>
then try setting it to .true. .<br>
<br>
when you update you should see modified CHANGELOG and<br>
assimilation_code/modules/assimilation/assim_tools_mod.f90 files.<br>
<br>
if you have any questions or concerns, please write <a class="moz-txt-link-abbreviated" href="mailto:dart@ucar.edu">dart@ucar.edu</a><br>
<br>
thanks, and have a good weekend.<br>
nancy<br>
<br>
<br>
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<br>
<br>
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