Section: 4.5 Using SMC's built-in CPU-usage functionality
Scali MPI Connect Release 4.4 Users Guide 45
4.5 Using SMC's built-in CPU-usage functionality
Scali MPI Connect has the capability to report wall clock time, and user and system CPU time
on all processes with a built-in CPU timing facility. To use SMC's built-in CPU-usage-timing it is
necessary first to set the environment variable SCAMPI_CPU_USAGE.
The information displayed is collected with the system-call "times"; see man-pages for more
information.
The output has two different blocks. The first block contains CPU-usage by the sub monitors on
the different nodes. One line is printed for each sub monitor followed by a sum-line and an
average-line. The second block consists of one line per process followed by a sum-line and an
average-line.
For example, to get the CPU usage when running the image enhancement program do:
user% SCAMPI_CPU_USAGE=1 mpirun -np 4 ./kollektive-8 ./uf256-8.pgm
This produces the following report:
---------- Own ----------- ------ Own+Children ------
Submonitor timing stat. in secs Elapsed User System Sum User System Sum
Submonitor-1@r9 2.970 0.000 0.000 0.000 0.090 0.030 0.120
Submonitor-2@r8 3.250 -0.000 0.000 -0.000 0.060 0.040 0.100
Submonitor-3@r7 3.180 -0.000 -0.000 -0.000 0.050 0.030 0.080
Submonitor-4@r6 3.190 0.010 0.000 0.010 0.090 0.020 0.110
Total for submonitors 12.590 0.010 -0.000 0.010 0.290 0.120 0.410
Average per submonitor 3.147 0.003 -0.000 0.003 0.073 0.030 0.103
---------- Own -----------
Process timing stat. in secs Elapsed User System Sum
kollektive-8-0@r9 0.080 0.070 0.030 0.100
kollektive-8-1@r8 0.050 0.020 0.040 0.060
kollektive-8-2@r7 0.050 0.020 0.030 0.050
kollektive-8-3@r6 0.010 0.020 0.020 0.040
Sum for processes 0.190 0.130 0.120 0.250
Average per process 0.048 0.033 0.030 0.062
Elapsed is walltime used by user-process/submonitor
User is cpu-time used in user-process/submonitor
System is cpu-time used in system-calls
Sum is total cpu-time used by user-process/submonitor