gprof

问题 This question already has answers here : Function execution time (2 answers) Closed 5 years ago . I want to find out the time spent by a particular function in my program. FOr that purpose, I am making use of gprof. I used the following command to get the time for the specific function but still the log file displays the results for all the functions present in the program. Please help me in this regard. gprof -F FunctionName Executable gmon.out>log 回答1: You are nearly repeating another

问题 I'm having trouble running gprof on OS X. The file test.c is: #include <stdio.h> int main() { printf("Hello, World!\n"); return 0; } and my terminal looks like: $ gcc -pg test.c $ gcc -pg -o test test.c $ ./test Hello, World! $ gprof test gprof: file: test is not of the host architecture Edit: also, it doesn't generate the file gmon.out . What's going on here? 回答1: The series of events here is supposed to work as follows: Compile code with -pg option Link code with -pg option Run program

问题 This question already has answers here : Why does the order of the loops affect performance when iterating over a 2D array? (7 answers) Closed 5 years ago . I am given two functions for finding the product of two matrices: void MultiplyMatrices_1(int **a, int **b, int **c, int n){ for (int i = 0; i < n; i++) for (int j = 0; j < n; j++) for (int k = 0; k < n; k++) c[i][j] = c[i][j] + a[i][k]*b[k][j]; } void MultiplyMatrices_2(int **a, int **b, int **c, int n){ for (int i = 0; i < n; i++) for

问题 This question already has answers here : Why does the order of the loops affect performance when iterating over a 2D array? (7 answers) Closed 5 years ago . I am given two functions for finding the product of two matrices: void MultiplyMatrices_1(int **a, int **b, int **c, int n){ for (int i = 0; i < n; i++) for (int j = 0; j < n; j++) for (int k = 0; k < n; k++) c[i][j] = c[i][j] + a[i][k]*b[k][j]; } void MultiplyMatrices_2(int **a, int **b, int **c, int n){ for (int i = 0; i < n; i++) for

问题 I would like to use gprof to profile a daemon. My daemon uses a 3rd party library, with which it registers some callbacks, then calls a main function, that never returns. I need to call kill (either SIGTERM or SIGKILL) to terminate the daemon. Unfortunately, gprof's manual page says the following: The profiled program must call "exit"(2) or return normally for the profiling information to be saved in the gmon.out file. Is there is way to save profiling information for processes which are

问题 I would like to use gprof to profile a daemon. My daemon uses a 3rd party library, with which it registers some callbacks, then calls a main function, that never returns. I need to call kill (either SIGTERM or SIGKILL) to terminate the daemon. Unfortunately, gprof's manual page says the following: The profiled program must call "exit"(2) or return normally for the profiling information to be saved in the gmon.out file. Is there is way to save profiling information for processes which are

问题 I am trying to optimize a c++ program's performance and reduce its run time. However, I am having trouble figuring out where is the bottleneck. time command shows that the program itself takes about 5 minutes to run, and about the 5 minutes, user cpu time takes 4.5 minutes. CPU profiler (both gcc profiler and google perftool) shows that the function calls only take 60 seconds in total in CPU time. I also tried to use the profiler to sample real time instead of cpu time, and it gives me

问题 I am trying to optimize a c++ program's performance and reduce its run time. However, I am having trouble figuring out where is the bottleneck. time command shows that the program itself takes about 5 minutes to run, and about the 5 minutes, user cpu time takes 4.5 minutes. CPU profiler (both gcc profiler and google perftool) shows that the function calls only take 60 seconds in total in CPU time. I also tried to use the profiler to sample real time instead of cpu time, and it gives me

问题 How can we list all the functions being called in an application. I tried using GDB but its backtrace list only upto the main function call. I need deeper list i.e list of all the functions being called by the main function and the function being called from these called functions and so on. Is there a way to get this in gdb? Or could you give me suggestions on how to get this? 回答1: How can we list all the functions being called in an application For any realistically sized application, this

问题 In multiple run of my C program with different parameter values, I get multiple profiling report files. This is too difficult to read and compare. Is there a way I can get a comparison file, preferably with graphs to show , how the performance increased or decreased as the size (the parameter that i am passing at the run time ) is increased. 回答1: Try perf(1) tool. perf record ./yourbinary perf record ./yourbinary-v2 perf diff Having compiler options "-O0 -g -ggdb" around when making binaries