In this article, we will explore the GNU profiling tool ‘gprof’. In this step, the gprof tool is run with the executable name and the above. What is gprof? Gprof is a profiling program which collects and arranges statistics on your programs. Write hate-mail to gnu (but don’t tell them I told you to). Table of Contents. 1. Introduction to Profiling · 2. Compiling a Program for Profiling · 3. Executing the Program · 4. gprof Command Summary · Output Options.

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Table of Contents

Could you please add details about how to get gmon. While flat profile gives an overview of the timing information of the functions like time consumption for the execution of a particular function, how many times it was called etc. This produces an analysis file which contains all the desired profiling information. In this first step, we need to make sure that the profiling is enabled when the compilation of the code is done. gpro

That program counter sampling is useful as opposed to stack sampling. If you simply want to know which functions burn most of the cycles, it is stated concisely here. I will be posting instruction guides, how-to, troubleshooting tips and tricks on Linux, database, hardware, security and web.

You can also simply drop me a line to say hello!. Note that one can explicitly specify the output file like in example above or the information is produced on stdout.


In other words, in the hands of an experienced programmer, it is a very valuable tool for exactly what you claim it isn’t good for. As usual in life, it is a matter of using the tool in the right way in addition to using the right tool and that involves having enough experience in order to interpret it you know, sort of like you don’t use a hammer to put a screw in a screw hole?

This helps make your program execution faster which is always desired. Instrumentation code is automatically inserted into the program code during compilation for example, by using the ‘-pg’ option of the gcc compilerto gather caller-function data.

In very large projects, profiling can save your day by not only determining the parts in your program which are slower in execution than expected but also can help you find many other statistics through which many potential bugs can be spotted and sorted out.

Several gmon files can be combined with ‘gprof -s’ to gnnu data from several runs of a program.

Unlike prof, gprof is capable of limited call graph collecting and printing. You must use this option when compiling the source files you want data about, and you must also use it when linking. At run-time, timing values are obtained by statistical sampling.

That the call graph is important as gprov to the information in stack samples. Dario August 13,8: I think it is better to make bigger time discrete in functions. The call graph shows, for each function, which functions called it, which other functions it called, and how many times.

GNU gprof – Table of Contents

Hi Is it possible to set the gmon. That samples need not be taken during IO or other blockage as opposed to sampling on wall-clock time. The individual columns for the flat profile as well as call graph are very well explained in the output itself.


In some versions, such as BSD, profiling of shared libraries can be limited because of restrictions of the profil function, which may be implemented as library function or as system call. The man page, by the way, suggests gnnu Sorry for bad English and thank you very much for this article. Thank you very much, keep up the good work!

That recursion is a tricky confusing issue it only is a problem when trying to construct an annotated call graph. My focus is to write articles that will either teach you or help you resolve a problem. Lets have a look at this text file:.

Notify me of followup comments via e-mail. From GProf to DTrace “2. A call to the monitor function grof is inserted before each function call.

GPROF Tutorial – How to use Linux GNU GCC Profiling Tool

It is easy to use,clearly and instructive. Vivek Kumar December 30,9: Anyway, as for why it would hang, a question and a suggestion on gnk out where its having issues:. Read more about Ramesh Natarajan and the blog. GPROF output consists of two parts: Ehsan March 16,7: