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--- user_guide:extend:profiling [2019/01/30 14:44] – deleted artefact from move operation (i think). current page at user_guide:extend:profiling oroehrig
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+===== Profiling  =====
+This page describes two different ways how you can analyze and profile your code in ''polymake''.
+==== using valgrind ====
+Using the tool [[http://valgrind.org/|valgrind]] is an easy way to get many pieces of information about your code.
+Once valgrind is installed on your system you are able to use many analyzing tools, as callgrind and cachegrind.
+You will find more details in the [[http://valgrind.org/docs/manual/manual.html|manual]].
+You can run ''polymake'' and your code with valgrind via the command
+<code>
+valgrind --tool=callgrind perl/polymake
+</code>
+or your corresponding path to ''polymake''.
+''polymake'' will start and you can execute your code, while valgrind is collecting data.
+But be aware that this will slow down your program, such that you should just test your code with very small examples.
+A typical shell output looks like this:
+<code>
+==30738== Callgrind, a call-graph generating cache profiler
+==30738== Copyright (C) 2002-2009, and GNU GPL'd, by Josef Weidendorfer et al.
+==30738== Using Valgrind-3.6.0.SVN-Debian and LibVEX; rerun with -h for copyright info
+==30738== Command: perl/polymake
+==30738==
+==30738== For interactive control, run 'callgrind_control -h'.
+Welcome to polymake version 2.12.3, rev. 11104 [DEVELOPER MODE]
+Copyright (c) 1997-2012
+Ewgenij Gawrilow, Michael Joswig (TU Darmstadt)
+http://www.polymake.org
+This is free software licensed under GPL; see the source for copying conditions.
+There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+Press F1 or enter 'help;' for basic instructions.
+Application polytope currently uses following third-party software packages:
+cddlib, geomview, graphviz, jreality, lrslib, nauty, normaliz2, permlib, povray, qhull, sketch, sympol, tosimplex
+For more details:  show_credits;
+polytope > script("my_script.pl");
+polytope > exit;
+==30738==
+==30738== Events    : Ir
+==30738== Collected : 2091660153168
+==30738==
+==30738== I   refs:      2,091,660,153,168
+</code>
+After closing ''polymake'' you will find files called callgrind.out.*, where * is a session number. The file stores all information about the run, in the above example callgrind.out.30738. You can open the file using kcachegrind.
+Picture1
+In our example you can see from this file, that mostly called is the interior function ''_gmpz_mul'', as subroutine of ''dd_LPSolve_gmp''.
+This gives the hint that many Linear Programs will be solved that nearly all time is needed for that.
+Another useful tool is cachegrind. You can run your code similar to the above via the command
+<code>
+valgrind --tool=cachegrind perl/polymake
+</code>
+you will produce a file called cachegrind.out.* and also the shell output is similar.
+The data you will get tells you about the cach misses in your Program.
+A weak point of this methode is that also other information than your code is analyzed, as recompiling and the files which where execute by the start of
+''polymake''. You can start your code as [[:callable|Callable Library]] to reduces this.
+==== using gprof ====
+Another way is using [[http://sourceware.org/binutils/docs/gprof/|gprof]]. To run this we start our code as [[:callable|Callable Library]] and have to install ''polymake'' again, this time compiling under the flags '-g', '-pg' and '-O2'.
+You can change compiler flags in the file '/build.x86_64/conf.make'.
+It should look like this (with your corresponding paths):
+<code>
+...
+Cflags := -march=native -g -pg -Wall -I/.../mpfr/include
+CXXflags := -march=native -g -pg -ftemplate-depth-200 -Wall -Wno-strict-aliasing -Wno-parentheses -fno-inline-functions-called-once -I/.../mpfr/include
+...
+CXXOPT := -O2
+...
+LDflags :=  -g -pg -L/.../mpfr/lib -Wl,-rpath,/.../mpfr/lib
+LDsharedFlags := -shared -O2 -g -pg -L/usr/local/lib -fstack-protector
+LDcallableFlags := -shared -O2 -g -pg -L/usr/local/lib -fstack-protector  -fstack-protector -L/usr/local/lib
+...
+</code>
+For this version of ''polymake'' we execute our code as [[:callable|Callable Library]] also compiled under the flags '-g' and '-pg'. Therefore you can use the makefile from the [[http://polymake.org/lib/exe/fetch.php/callable.tbz|example]]. We execute our c++ program 'test' via the command
+<code>
+./test
+</code>
+This takes a while and produces the file 'gmon.out' which stores all profling data and can convert to a readable file via the command
+<code>
+gprof [executable file] [> Outfile]
+</code>