Collecting memory leaks

Collect is a command stat that we can use to collect memory leaks.

What makes it superior than others..?

If we go for dbx or any other Debugger in the IDE ,these tools will give larger data collection about memory leaks.But using Collect we can collect same memory leaks with smaller data collection.

Steps we need to do,

1. Run the program with debug option
   
   % CC -g -o test test.cc
2. Run time Data collection
   
   We are concern about memory leaks, so we have to turn the heap tracing on with -H option. By default, heap tracing is off.

% which collect
   
   /opt/SUNWspro/prod/bin/collect
   
   % collect -H on -o test.er test
   
   Creating experiment database test.er ...
   
   Address of x = 434323322, y = 434343434
   
   New address of x = 434343433, y = 434344444
   
   It creates the test.er experiment and archives the binary files describing each load object referenced in the loadobjects file.
   
3. Call the performance analyzer, er_print (command line tool) or analyzer (graphical tool)

   % er_print test.er
   
   
   
   (er_print) source allocate
   
   
   
   Source file: ./test.c
   
   
   
   Object file: ./test
   
   
   
   Load Object: ./test

example:

%>er_print mem.er

(er_print) source allocate

Source file: ./test.cc

Object file: ./test

Load Object: ./test

Incl. Incl.

Excl. Incl.

Bytes Leaks User CPU User CPU Leaked sec. sec.

Incl. Incl.

Excl. Incl.

Bytes Leaks User CPU User CPU Leaked sec. sec.

……………………………………………………………1. #include
……………………………………………………………2. using namespace std;
……………………………………………………………3. void allocate();
0 0 0. 0. …………………………………………………4. int main() {

## 1012 3 0. 0. ………………………………………....5. allocate();
0 0 0. 0. …………………………………………………6.return (0);
0 0 0. 0…………………………………………………..7. }
……………………………………………………………8.
0 0 0. 0. …………………………………………………9. void allocate() {
……………………………………………………………10. int *a;
……………………………………………………………11. char *b;
………………………………………………..…………..12.
0 0 0. 0……………………………...……………………13. a = (int *) malloc( 512);
512 1 0. 0……………………………………………… .14. b = (char *) malloc ( 512);
………………….………………………………………...15.
0 0 0. 0. ………………………………………….…….. 16. printf("\nAddress of a = %u, b = %u", a, b);
0 0 0. 0. …………………………………………………17. free(a);
250 1 0. 0………………………..…………………….. 18. a = (int *) malloc (250);
250 1 0. 0. ………………..…………………………….19. b = (char *) malloc (250);
0 0 0. 0. …………………………………………………20. printf("\nNew address of a = %u, a = %u\n", a, b);
0 0 0. 0. …………………………………………………21. }

WARNING: too few clock-profile events (1) in experiment 1 (`test.er') for statistical validity
Source:
http://docs.sun.com/source/819-0493/Collector.html#pgfId-1041571