Section: 4.5 Using SMC's built-in CPU-usage functionality

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:

Submonitor timing stat. in secs

---------- Own ----------- ------ Own+Children ------

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

Process

timing stat. in secs

Elapsed

----------

Own -----------

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

Scali MPI Connect Release 4.4 Users Guide

45

Page 57
Image 57
Escali 4.4 manual Using SMCs built-in CPU-usage functionality, This produces the following report