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Subject: Re: posix thread scaling issue
Thread-Topic: posix thread scaling issue
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Date: Sat, 2 Sep 2023 21:23:08 +0000
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Jeff wrote:

> Thanks. I am doing the memory allocation in a single thread.
> The compute uses all the threads I can get, and the compute isn't 
> scaling very well with cygwin.
> It does work well on my 16 core 32 thread processor, so for most people 
> the posix threading is fine.

> jeff


For the multi-threaded program that I wrote, with up to 64 threads, I compile each file with:

x86_64-w64-mingw32-c++ -O3 -c file.cpp

and link with:

x86_64-w64-mingw32-c++ -o program *.o -static-libgcc -static-libstdc++ -Wl,-Bstatic -lstdc++ -lpthread -Wl,-Bdynamic

And I get could results. 100% CPU use; I even need to lower the priority of the program to keep a snapy Windows UI.

You may try the same to see if it improves the performance of your program.

Regards,

- André Bleau

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