NAME

lmdbg - memory debugging tool

SYNOPSIS

lmdbg [OPTIONS] <prog> [args...]

DESCRIPTION

lmdbg runs an external program prog , collects run-time information and saves it to a specified log file. More particulary, lmdbg is able of: decoding all symbols in the source code (function names, file name and position in the file); discovering all memory leaks ( -M default ); finding per-stacktrace memory leaks and ranking them from the largest to the smallest ( -M leaks ); gathering (and ranking) various types of per-stacktrace run time statistics, such as the highest memory consumption ( -M peak ), the number of calls to memory allocation functions ( -M allocs ) and the highest size of memory allocated by a single invocation of malloc function ( -M max ). To accomplish the above tasks, lmdbg , as a meta tool, manages a set of low level lmdbg-* utilities, namely, lmdbg-run, lmdbg-leaks, lmdbg-sym, lmdbg-sysleaks, lmdbg-sort and lmdbg-stat.

OPTIONS

-h: Display the help message.
-V: Display the lmdbg version.
-o filename: Specify the log file to save data to.
-M mode: Specify the task to do, mode is either of the following:

d or default: Show all stacktraces with memory leaks. This is the default.
l or leaks: Rank stacktraces by memory leaks.
p or peak: Rank stacktraces by the peak memory consumption.
a or allocs: Rank stacktraces by the number of calls to memory allocation functions.
m or max: Rank stacktraces by the highest amount of memory allocated in a single invocation of malloc function.

-c filename: This option is passed to lmdbg-sysleaks(1).
-a: This option is passed to lmdbg-sym(1).
-g: This option is passed to lmdbg-sym(1).
-n: This option is passed to lmdbg-run(1).
-T num: This option is passed to lmdbg-run(1).
-B num: This option is passed to lmdbg-run(1).
-v: Enable verbose mode.

FILES

~/.lmdbg.conf or /usr/local/etc/lmdbg.conf: lmdbg configuration file

EXAMPLE

$ cat test3.c
#include <stdlib.h>
int main ()
{
   int i;
   void *p1, *p2;
   p1 = malloc (900);
   for (i=0; i < 3; ++i){
      p2 = realloc (NULL, 10+300*i);
   }
   free (p1);
   free (p2);
   return 0;
}
$ cc -O0 -g -o test3 test3.c
$ lmdbg -o log ./test3; cat log
realloc ( NULL , 10 ) --> 0xbb901040 num: 2
      lmdbg.c:140     log_stacktrace
      lmdbg.c:545     realloc
      test3.c:9       main
 
realloc ( NULL , 310 ) --> 0xbb912140 num: 3
      lmdbg.c:140     log_stacktrace
      lmdbg.c:545     realloc
      test3.c:9       main
 
$ lmdbg -M leaks -o log ./test3; cat log
info progname ./test3
info stat total_allocs: 2
info stat total_free_cnt: 0
info stat total_leaks: 320
stacktrace peak: 320 max: 310 allocs: 2 leaks: 320
      lmdbg.c:140     log_stacktrace
      lmdbg.c:545     realloc
      test3.c:9       main
 
$ lmdbg -M peak -o log ./test3; cat log
info progname ./test3
info stat total_allocs: 4
info stat total_free_cnt: 2
info stat total_leaks: 320
stacktrace peak: 930 max: 610 allocs: 3 leaks: 320
      lmdbg.c:140     log_stacktrace
      lmdbg.c:545     realloc
      test3.c:9       main
 
stacktrace peak: 900 max: 900 allocs: 1
      lmdbg.c:140     log_stacktrace
      lmdbg.c:509     malloc
      test3.c:7       main
 
$ lmdbg -M max -o log ./test3; cat log
info progname ./test3
info stat total_allocs: 4
info stat total_free_cnt: 2
info stat total_leaks: 320
stacktrace peak: 900 max: 900 allocs: 1
      lmdbg.c:140     log_stacktrace
      lmdbg.c:509     malloc
      test3.c:7       main
 
stacktrace peak: 930 max: 610 allocs: 3 leaks: 320
      lmdbg.c:140     log_stacktrace
      lmdbg.c:545     realloc
      test3.c:9       main
 
$ lmdbg -M allocs -o log ./test3; cat log
info progname ./test3
info stat total_allocs: 4
info stat total_free_cnt: 2
info stat total_leaks: 320
stacktrace peak: 930 max: 610 allocs: 3 leaks: 320
      lmdbg.c:140     log_stacktrace
      lmdbg.c:545     realloc
      test3.c:9       main
 
stacktrace peak: 900 max: 900 allocs: 1
      lmdbg.c:140     log_stacktrace
      lmdbg.c:509     malloc
      test3.c:7       main
 
$

AUTHOR

Aleksey Cheusov <vle@gmx.net>