profiler valgrind gprof strace ltrace gperftools gnu fortran c++ python openmp makefile cmake
Travis (.com) dev branch:
Flat profile:
Each sample counts as 0.01 seconds.
% cumulative self self total
time seconds seconds calls Ts/call Ts/call name
100.24 12.58 12.58 MAIN__
% the percentage of the total running time of the
time program used by this function.
cumulative a running sum of the number of seconds accounted
seconds for by this function and those listed above it.
self the number of seconds accounted for by this
seconds function alone. This is the major sort for this
listing.
calls the number of times this function was invoked, if
this function is profiled, else blank.
self the average number of milliseconds spent in this
ms/call function per call, if this function is profiled,
else blank.
total the average number of milliseconds spent in this
ms/call function and its descendents per call, if this
function is profiled, else blank.
name the name of the function. This is the minor sort
for this listing. The index shows the location of
the function in the gprof listing. If the index is
in parenthesis it shows where it would appear in
the gprof listing if it were to be printed.
Copyright (C) 2012-2018 Free Software Foundation, Inc.
Copying and distribution of this file, with or without modification,
are permitted in any medium without royalty provided the copyright
notice and this notice are preserved.
==========Build finished with-Ofast===================
6.0914725065231323E-002 0.0000000000000000 1.5476670116186142E-002
Flat profile:
Each sample counts as 0.01 seconds.
% cumulative self self total
time seconds seconds calls Ts/call Ts/call name
100.24 12.61 12.61 MAIN__
% the percentage of the total running time of the
time program used by this function.
cumulative a running sum of the number of seconds accounted
seconds for by this function and those listed above it.
self the number of seconds accounted for by this
seconds function alone. This is the major sort for this
listing.
calls the number of times this function was invoked, if
this function is profiled, else blank.
self the average number of milliseconds spent in this
ms/call function per call, if this function is profiled,
else blank.
total the average number of milliseconds spent in this
ms/call function and its descendents per call, if this
function is profiled, else blank.
name the name of the function. This is the minor sort
for this listing. The index shows the location of
the function in the gprof listing. If the index is
in parenthesis it shows where it would appear in
the gprof listing if it were to be printed.
Copyright (C) 2012-2018 Free Software Foundation, Inc.
Copying and distribution of this file, with or without modification,
are permitted in any medium without royalty provided the copyright
notice and this notice are preserved.
==========Build finished with-O3===================
Optimization Level
Compile only. Default: -o2
GFortran options: -o0, -o1, -o2, -o3, -os, -ofast
Specify -o0 to disable optimizations.
Specify -o1 to perform level-1 optimizations.
Specify -o2 to perform level-2 optimizations.
Specify -o3 to perform level-3 optimizations.
Specify -os to optimize for size.
Specify -ofast to perform level-3 optimizations plus disregard strict standards compliance.
Note that -o3 or -ofast can cause your program to require more stack at runtime. If your program exceeds the maximum amount of stack at runtime, increase the stack by using the -stack option.
http://www.lahey.com/docs/lgf13help/LFCOO0O1.htm
Output flags
Warning flags
Fortran dialect flags
-fopenmp: Tells gfortran to compile using OpenMP. Without this flag, OpenMP directives in your code will be ignored.
-std=f95: Enforces strict compliance with the Fortran 95 standard. This is like -pedantic, except it generates errors instead of warnings.
Debugging flags
Optimization flags
https://faculty.washington.edu/rjl/uwamath583s11/sphinx/notes/html/gfortran_flags.html
GNU Fortran
https://gcc.gnu.org/fortran/
The application programming interface (API) OpenMP (Open Multi-Processing) supports multi-platform shared-memory multiprocessing programming in C, C++, and Fortran,[3] on many platforms, instruction-set architectures and operating systems, including Solaris, AIX, HP-UX, Linux, macOS, and Windows. It consists of a set of compiler directives, library routines, and environment variables that influence run-time behavior.
https://www.openmp.org/
strace is a diagnostic, debugging and instructional userspace utility for Linux
https://strace.io/
ltrace is a debugging utility in Linux, used to display the calls a userspace application makes to shared libraries.
https://en.wikipedia.org/wiki/Ltrace
gperftools is a collection of a high-performance multi-threaded malloc() implementation, plus some pretty nifty performance analysis
tools
https://github.com/gperftools/gperftools
Gprof is a performance analysis tool for Unix applications.
https://en.wikipedia.org/wiki/Gprof
Valgrind is an instrumentation framework for building dynamic analysis tools. There are Valgrind tools that can automatically detect many memory management and threading bugs, and profile your programs in detail. You can also use Valgrind to build new tools.
It runs on the following platforms:
X86/Linux, AMD64/Linux, ARM/Linux, ARM64/Linux, PPC32/Linux, PPC64/Linux, PPC64LE/Linux, S390X/Linux, MIPS32/Linux, MIPS64/Linux, X86/Solaris, AMD64/Solaris, ARM/Android (2.3.x and later), ARM64/Android, X86/Android (4.0 and later), MIPS32/Android, X86/Darwin and AMD64/Darwin (Mac OS X 10.12).
https://valgrind.org/
GDB, the GNU Project debugger, allows you to see what is going on `inside' another program while it executes -- or what another program was doing at the moment it crashed
http://www.gnu.org/software/gdb/
https://www.onlinegdb.com/