Better balance the cell load between ranks

applications/poisson_dg/poisson_dg.mini

@@ -11,15 +11,20 @@ ranks = 16
 floatingbytes = 8
 
 # Metaini Calculations
-totalmem = {mbperrank} * 1048576 * {ranks} | eval
+memperrank = {mbperrank} * 1048576 | eval
 dofsperdir = {formcompiler.ufl_variants.degree} + 1 | eval
 celldofs = {dofsperdir} ** {dim} | eval
-totalcells = {totalmem} / ({floatingbytes} * {celldofs}) | eval
-cellsperdir = {totalcells} ** (1/{dim}) | eval | toint
+cellsperrank = {memperrank} / ({floatingbytes} * {celldofs}) | eval
+cellsperdir = {cellsperrank} ** (1/{dim}) | eval | toint
+firstdircells = {ranks} * {cellsperdir} | eval
+dimminusone = {dim} - 1 | eval
+ones = 1 | repeat {dimminusone}
+otherdircells = {cellsperdir} | repeat {dimminusone}
 
 # Setup the grid!
 extension = 1.0 | repeat {dim}
-cells = {cellsperdir} | repeat {dim}
+cells = {firstdircells} {otherdircells}
+partitioning = {ranks} {ones}
 
 [wrapper.vtkcompare]
 name = {__name}