Activate report grid memory consumption

[ykempf]

Just for laughs? How long has this not been used? Not like I just spent a number of weeks looking into memory consumption...........

[ykempf]

Suggestion from Markus: implement a similar memory report functionality for fsgrid. Not today.

[ykempf]

Example output:

(MEM) tstep 0 t 0 Resident per node (avg, min, max): 2.1022 2.1022 2.1022
(MEM) tstep 0 t 0 High water mark per node                 (GiB) avg: 2.1022 min: 2.1022 max: 2.1022 sum (TiB): 0.00205293 on 1 nodes
(MEM) Total size: 1.46364e+08
(MEM) Total capacity 1.58685e+08
(MEM)   Average capacity: 9.91781e+06 local cells 1.8856e+06 remote cells 8.0322e+06
(MEM)   Max capacity:     1.25012e+07 on  process 6
(MEM)   Min capacity:     7.54602e+06 on  process 2

So let's discuss if we want more info (value and rank of local vs. remote cells' min and max capacity?), and in what format/ordering.

And also, this should list explicitly that we're talking of the spatial cells here, especially if/when we extend this to also report fsgrid memory usage.