Linux Performance Optimization Tool gprof précis-writers

1. Gprof How to work

   When you specify the-PG option when using GCC compilation, the compiler inserts the performance test code into the user code.

   
   

2. Gprof Simple Application Example

   Main.c

#include <stdio.h> #include "lib.h" int main (void) {func1 (FUNC2); return 0;}

Lib.h

#ifndef lib_h#define lib_hvoid func1 (int i), void func2 (int i); #endif/* Lib_h */

Lib.c

#include <stdio.h> #include "lib.h" void func1 (int i) {while (i--) printf ("Func1 ():%d\n", i);} void Func2 (int i) {while (i--) printf ("Func2 ():%d\n", i);}

Makefile

CFLAGS + =-PGOBJS = $ (patsubst%.c,%.o,$ (wildcard *.c)) Prog: $ (OBJS) gcc-pg-o [email protected] $^clean:-rm-f prog $ (obj S

Run make compile code at the command line to generate the prog file. Enter the./prog to run the file, producing an output file gmon.out. After

Use the tool gprof to analyze the operation of the output File Analyzer and to derive the data optimizer based on these analyses.

Run the Gprof prog gmon.out > Gprofrslt.txt analysis output file to get the following results (excerpt). can be passed to

Gprof different parameters to derive the output of different aspects of performance considerations.

flat profile:each sample counts as 0.01 seconds. no time  accumulated  %   cumulative   self               self     total             time   seconds   seconds     calls  Ts/call  Ts/call  name       0.00      0.00     0.00         1     0.00     0.00   func1  0.00      0.00     0.00         1     0.00      0.00  func2

The meaning of the specific output can be referenced in the GPROF help documentation.

3. Gprof Documentation

http://sourceware.org/binutils/docs/gprof/

This article is from the "Jimokuangxiangqu" blog, make sure to keep this source http://4594296.blog.51cto.com/4584296/1841733

Linux Performance Optimization Tool gprof précis-writers