Gprof is a performance analysis tool for Unix applications. It used a hybrid of instrumentation Another implementation was written as part of the GNU project for GNU GPROF output consists of two parts: the flat profile and the call graph. Gprof is a profiling program which collects and arranges statistics on your lly, it looks Write hate-mail to gnu (but don’t tell them I told you to). If you are a programmer, who writes code in C, Pascal, or Fortran77 programming language and uses Linux as the development platform, youll be glad to.

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Unlike prof, gprof is capable of limited call graph collecting and printing. Yes, my password is: Sampling data is saved in ‘gmon.

Functions which consume a large fraction of the run-time can be identified easily from the output of gprof. In this tutorial, we’ll be discussing the details of how you can download, install, and use this tool.

It can be analyzed with gprof by giving the name of the executable as an argument:. GPROF output consists of two parts: This creates an instrumented executable which contains additional instructions that record the time spent in each function. Needless to say, the best way to understand a tool like Gprof is through a practical example. Download and Install Gprof Gprof Usage.

From Wikipedia, the free encyclopedia. Armed with this information, now you’ll be in a better position to understand the data present in your profiling output file profile-data.

The next step is to launch that executable. Views Read Edit View history. So, we’ll start off with a C language program, which we’ll be profiling through Gprof. Now, moving on, the next step is to compile this code using gcc. So, what exactly is Gprof? Sampling is done by probing the target program’s program counter at regular intervals using operating system interrupts programmed via profil 2 or setitimer 2 syscalls.


Gough, foreword by Richard M. Note that ideally I would have compiled the above code using the following command:. If the program consists of more than one source file then the -pg option should be used when compiling each source file, and used again when linking the object files to create the final executable as shown above.

Retrieved from ” https: However, whatever we’ve covered here should be enough to get you started. Before we move ahead, please note that all the examples and instructions mentioned in this tutorial have been tested on Ubuntu Several gmon files can be combined with ‘gprof -s’ to accumulate data from several runs of a program.

There is an external tool called gprof2dot capable of converting the call graph from gprof into graphical form.

How to install and use profiling tool Gprof on Linux

The second part of the output is the textual call graph, which shows for each function who called it parent and who it called child subroutines. In case you want this information to be omitted from the output, you can use the -b option provided by Gprof.

If broken down to the last bit, performance testing effectively tests how profileer time a particular piece of code – say a function – is consuming. Webarchive template wayback links. Here’s the flat profile in my case:.

An Introduction to GCC – Using the profiler gprof

Function call counts are also reported. A Selection, Kathryn S. In case you already use Gprof, and want to share something related to the tool with everyone here, just bnu in a comment below. Consequently efforts to decrease the run-time of the program should concentrate on the former. While running the instrumented executable, profiling data is silently written to a file ‘gmon.


Once the command is executed, you’ll see that a file named gmon. Here’s how I launched the binary in my case: There’s no doubt that testing is an integral and one of the most important aspects of the software development process.

If a value is n times the sampling period, the expected error in the value is the square root of n sampling periods.

As is usually the case, a function or a group of functions may correspond to one of the many features of a software. So, gun use the Gprof tool in the following way:.

How to install and use profiling tool Gprof on Linux

profuler This page was last edited on 21 Decemberat There were analogous utility in glibc called ‘sprof’ to profile dynamic libraries. Cycles are discovered, and calls thee a cycle are made to share the time of the cycle. Gprof is a performance analysis tool for Unix applications. A call to the monitor function ‘mcount’ is inserted before each function call. If you’re wondering about the source of above screenshots, let me tell you that all this information is there in the output file that contains the profiling information, including flat profile and call graph.

The other columns in the output provide information on the total number of function calls made, and the time spent in each function. The GNU profiler gprof is a useful tool for measuring the performance of a program–it records the number of calls to each function and the amount of time spent there, on a per-function basis.