profilergperftools

Using GPerf Tool: not working, issue with redirection?

I'm trying to profile my software in order to optimize it.

I used gprof with the compilation flag -g -pg -O3 but the result are not giving me enough precision.

Here is my Stacktrace of compilation: 

$: make clean; make;

rm -f ./obj/*.o
rm -f ./bin/mdk-verifier
rm -f ./grammar/modal.output
rm -f ./grammar/modal.tab.h
rm -f ./grammar/*.cpp
rm -f ./lex.backup

bison -d -t -l -v -o ./grammar/modal.tab.c ./grammar/modal.y && mv ./grammar/modal.tab.c ./grammar/modal.tab.cpp
g++ -O3 -g -pg -fPIC -std=c++11  -I./include -c ./grammar/modal.tab.cpp -o ./obj/modal.tab.o
flex -l -b -o./grammar/lex.yy.cpp ./grammar/modal.lex   
g++ -O3 -g -pg -I./include -c ./grammar/lex.yy.cpp -o ./obj/lex.yy.o
g++ -O3 -g -pg -fPIC -std=c++11  -I./include -c ./src/Kripke.cc -o ./obj/Kripke.o   
g++ -O3 -g -pg -fPIC -std=c++11  -I./include -c ./src/Term.cc -o ./obj/Term.o 
g++ -O3 -g -pg -fPIC -std=c++11  -I./include -c ./src/BooleanConstant.cc -o ./obj/BooleanConstant.o 
g++ -O3 -g -pg -fPIC -std=c++11  -I./include -c ./src/Variable.cc -o ./obj/Variable.o 
g++ -O3 -g -pg -fPIC -std=c++11  -I./include -c ./src/PropositionalVariable.cc -o ./obj/PropositionalVariable.o 
g++ -O3 -g -pg -fPIC -std=c++11  -I./include -c ./src/Operation.cc -o ./obj/Operation.o 
g++ -O3 -g -pg -fPIC -std=c++11  -I./include -c ./src/BooleanOperation.cc -o ./obj/BooleanOperation.o 
g++ -O3 -g -pg -fPIC -std=c++11  -I./include -c ./src/ModalOperation.cc -o ./obj/ModalOperation.o   
g++ -O3 -g -pg -fPIC -std=c++11  -I./include -c ./src/Formula.cc -o ./obj/Formula.o 
g++ -O3 -g -pg -fPIC -std=c++11  -o ./obj/Main.o -c ./src/Main.cc 
g++ -O3 -g -pg -static -lprofiler -o ./bin/mdk-verifier ./obj/modal.tab.o ./obj/lex.yy.o ./obj/Kripke.o ./obj/Term.o ./obj/BooleanConstant.o ./obj/PropositionalVariable.o ./obj/Variable.o ./obj/Operation.o ./obj/BooleanOperation.o ./obj/ModalOperation.o ./obj/Formula.o ./obj/Main.o

And here is how I call my program: 

$: ./bin/mdk-verifier ./problem.txt < solution.txt

So after execution, everything is fine, I get a gmon.out file. I'm executing the command gprof ./bin/mdk-verifier | more and I get the following results:

Each sample counts as 0.01 seconds.
  %   cumulative   self              self     total           
 time   seconds   seconds    calls  ms/call  ms/call  name    
 34.00      2.13     2.13       18   118.33   118.33  ModalOperation::checkBranch(Kripke&, unsigned int)
  ...
  ...
  5.91      4.98     0.37 54684911     0.00     0.00  BooleanOperation::checkBranch(Kripke&, unsigned int)
  4.63      5.27     0.29 54684911     0.00     0.00  PropositionalVariable::checkBranch(Kripke&, unsigned int)

And obviously, the count of calls for ModalOperation::checkBranch overflowed... and by making a display everytime I'm entering this function, I indeed made more than 18 calls...

So I thought about using another profiler, more precise and I found GPerfTools by Google.

I wanted to use it, I installed on my Ubuntu:

and by following the tutorial, They asked me to set the environment variable CPUPROFILE

I did and I get: 

 $: env | grep "CPU"
 CPUPROFILE=./prof.out

I also put -lprofiler during the linking of my executable, So I thought that everything was okay and that I could start profiling the data in the file ./prof.out

But unfortunately, this file is not appearing... Nothing is created, so I can't profile anything...

Does anyone has an idea about why the ./prof.out file is not created and why the profiling is not gathering data ?

Thanks in advance for your help !

Best Regards;

Solution

  • Your purpose is to save time in your software. Multiple issues, first the negatives:

    Now for the positive: