profiling function call in backgroundpool
显示 更早的评论
I have two versions of my function (OLD and NEW).
I am trying to optimize the speed of my code. In normal mode, NEW runs faster than OLD.
When I use parfeval to run the functions in the backgroundpool, OLD is faster than NEW.
How can I find out what slows down NEW in the backgroundpool?
3 个评论
Rik
2025-2-27
I created my own code coverage and timing tool, because I have code branches for old Matlab releases and for GNU Octave. It is fairly slow and imprecise, which is why I wouldn't call it a profiling tool.
You could consider doing something like that yourself. One idea would be to have a function with a persistent variable log the time spent on specific lines (either with tic and toc, or with clock). Just before the worker shuts down you write this log to file. Have a each worker generate a unique file name to avoid file conflicts. You can then tabulate the results.
My tool works a bit like that (it also includes a dbstack call to help me track subfunction calls). I hope someone suggests a better way to do this so I can steal that idea.
Oliver Jaehrig
2025-2-27
Can you check if you can use:
Rick Amos
2025-2-27
The mpiprofile feature is not yet supported for thread-based pools, however the underlying profile feature has been since R2023b. If you have R2023b or later, you can do the following to profile code running on the background until we do have something like mpiprofile:
info = fetchOutputs(parfeval(backgroundPool, @profileMyExample, 1));
profview(0, info);
function info = profileMyExample
profile("on");
runMyExample;
profile("off");
info = profile("info");
end
function runMyExample
% Some code to be profiled
for ii = 1:10
eig(rand(1000));
end
end
In terms of the differences in performance, the main suspect would be whether the function is itself implicitly multi-threaded and something changed when running from the background. If you do maxNumCompThreads(1), does the performance match between running normally and running in the background?
采纳的回答
更多回答（0 个）
类别
在 帮助中心 和 File Exchange 中查找有关 Programming Utilities 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
Translated by 
