[Dune] [#424] Data decomposition in YaspGrid is not optimal

[Dune]

THIS IS AN AUTOMATED MESSAGE, DO NOT REPLY.

A new Flyspray task has been opened.  Details are below. 

User who did this - Markus Blatt (mblatt) 

Attached to Project - Dune
Summary - Data decomposition in YaspGrid is not optimal
Task Type - Bug Report
Category - Grid
Status - New
Assigned To - 
Operating System - Unspecified / All
Severity - Low
Priority - Normal
Reported Version - SVN
Due in Version - Undecided
Due Date - Undecided
Details - Yaspgrid uses Torus<dim>::optimize_dims() to compute how to distribute the processors onto the grid.

Unfortunately the resulting distribution is far from optimal in some cases.

Calculating the distribution of 20 processors for a grid of dim=3 and size=[125 125 125] leads to the
following mapping

Torus<3>: mapping 20 processes onto 20 1 1 torus.

I would rather expect 5 4 1 instead which would leads to less imbalance (Just 
3125 instead of 15625 elements difference between some processors)

With increasing diensions the load imbalances become even more annoying.

More information can be found at the following URL:
http://www.dune-project.org/flyspray/index.php?do=details&task_id=424

You are receiving this message because you have requested it from the Flyspray bugtracking system.  If you did not expect this message or don't want to receive mails in future, you can change your notification settings at the URL shown above.