[CIG-SHORT] Understanding the memory usage

[Hongfeng Yang]

Hi all,

After a simulation, I read the memory usage summary from the running 
output as the following:

Memory usage is given in bytes:

Object Type          Creations   Destructions     Memory Descendants' Mem.
Reports information only for process 0.

--- Event Stage 0: Main Stage

               Vector     0             30     14829024     0
       Vector Scatter     0              6         6216     0
               Viewer     1              0            0     0

--- Event Stage 1: Meshing


--- Event Stage 2: Setup

               Vector    76             51      9908736     0
       Vector Scatter    12              8         8288     0
               Viewer     8              3         2040     0
            Index Set    24             24        17856     0

--- Event Stage 3: Reform Jacobian


--- Event Stage 4: Reform Residual


--- Event Stage 5: Unknown


--- Event Stage 6: Prestep


--- Event Stage 7: Step

               Vector     2              0            0     0

--- Event Stage 8: Poststep

               Vector    20             12      8623544     0
       Vector Scatter     4              2         2072     0
            Index Set     8              8         5952     0

--- Event Stage 9: Finalize

               Vector     0              5         7520     0
               Viewer     0              5         3400     0

The accumulated memory usage is about 34 M according to the above info. 
However, looking up the memory usage from "top" on my machine, every 
single run takes about 3% of the total memory, which is 24 G. That gives 
an estimation of 720 M per core, a big difference from the Pylith output.

Which one really tells me the real memory usage of Pylith? Or am I 
reading something wrong?

Thanks,

Hongfeng



-- 
Postdoc Investigator
Woods Hole Oceanographic Institution
Dept. Geology and Geophysics
360 Woods Hole Rd, MS 24
Woods Hole, MA 02543