My IDE is Visual Studio 2010 with integrated Intel Fortran compiler. The version of compiler is: Intel Parallel Studio XE 2011
I have intention to write in Output.txt file some interesting things from program execution. In this case i want to write program execution time, or execution time for specific do loop or specific do while iteration loop because I want to know how much time every single loop takes.
Is there any way for doing that?
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I need to find which parts of the code are taking more CPU time and whether I can improve those parts. I can define a timer object in the code but the compilation of the code after each modification is taking too much time and I cannot continue this way.
I do not use VB but I found some information on measuring and monitoring tools on the code performance inside VB.
Is there a way to find the cost of each line of the code while executing step by step or between breakpoints in debugging mode using CLion IDE to pinpoint the parts that are taking more CPU time to execute?
Take a look here: https://www.jetbrains.com/help/clion/cpu-profiler.html
CLion has an integration for perf (on Linux) and DTrace (on MacOS). Windows unfortunately doesn't provide profiling support at the operating system level, so you'll have to install a third-party profiler and won't be able to use it from within CLion. Your CPU manufacturer (AMD or Intel) provides one: Intel's is called VTune, AMD's is called µProf.
I am working with a FORTRAN.77 program with a lot of iterations in a lot of loops in Ubuntu/Linux with gfortran, and to compile and execute it I simply use
gfortran program.f
./executable.out
By using htop while the execution, I see only one of the cores is working on that process.
Is there any option/flag one can use in the compilation or in the execution to force it to use more than one core/thread so it will be much faster?
I have a multi-threaded programs. We use an own implementation of the thread pool. First, the load of the project is enough. compred to single thread, the program of two threads is more faster.
When we increase the number of threads, greater than 2, performance begins terrible. Obviously, we encountered a multi-threaded performance issues.
Then, we started using Intel® VTune ™ Amplifier XE 2017 Performance analysis, we put this tool integrated into the VS2013. Then a surprising thing happened when I click on the star button of Intel® VTune ™ Amplifier XE , the project begins to run, plug collects Data . We find that when we start this project through the plug-in, with the increase in the number of threads, the performance becomes higher, the running time is shortened. We can open up to 20 threads. And time is shortened 20 times
So, we want to know, can Intel® VTune ™ Amplifier XE 2017 change the operation mode of multithreaded programs ? Why does this happen.
I have been troubled by this problem for a long time.
Finally,I resolve this question.The answer is simple.The cause of problem is that I run the program with debugging.If I redirectly run the *.exe，the perfomance is well.There is no relationship to VTune,just beacause VTune directly start with calling *.exe.
I have a long C++ program consisting of thousands of lines of codes, several classes, functions etc. The program basically reads info from an input file, runs an algorithm, and writes the results in output files.
Today I realized that run time of the program drastically changes from time to time. So I do a small test by restarting my computer, closing every other thing possible, and running the code 5 times in a row using the same input file. The run times are 50, 80, 130, 180, 190 seconds, respectively.
My first guess in this situation is the non-deleted dynamic memories. But I have been using dynamic arrays just twice in the whole code, and I am sure I delete those arrays.
Do you guys have any explanation for this? I am using Visual Studio 2010 on Windows 7 computer.
Beware running programs from within visual studio debugger as the LFH (low fragmentation heap) memory allocator is disabled in this case. Try the software from outside of VS.
I have seen cases where tasks would take seconds to complete normally take hours to complete just by running from within visual studio.
Above all if you still don't know what is going on divide and conquer. Instrument the app to see runtimes of subsystems or just place debug timers in various areas to see where execution time is changing drastically and drill down from there. If it is a memory allocator issue you will normally see large runtimes while freeing the arrays.
Your code runs in an environment, which includes the state of the operating system, disk, network, time, memory, other processes launched, etc.
Executing the same code in the same environment will give the same result, every time.
Now, you're getting different results (execution times). If you're running the same executable repeatedly, then something is changing in the surrounding environment.
Now, the most obvious question is : Is your code causing a change to the outside environment? A simple example would be: It reads in a file, changes the data and writes it back out to the same file.
You know your code. Just use this approach to isolate any effects your code may be having on its environment and you'll find the reason.
I am profiling C++ using an instrumenting profiler from Microsoft (VSPerf) and converting the .vsp report file to .csv using VSPerfReport. In Report_FunctionSummary.csv the exclusive and inclusive times are the same for functions which do call other functions in the same object file. Is this a known problem and how can it be solved? I'm using Visual Studio 2008.
Inclusive time is exclusive time plus time in callees. So if a routine has no callees, inclusive time equals exclusive time. It will also be equal if the routine did call other routines but the profiler could not see those other routines.