Hello, Being a programmer myself I realise that a report on performance degradation should ideally contain a small test program that clearly reproduces the problem. However, unfortunately, I do not have the time at present to isolate the issue to a small test case. But the good news (or bad news, I suppose) is that the problem appears to be reasonably general, namely it happens with two completely different programs.
Anyway, what I am claiming is that Python 3.10 is between 1.5 and 2.5 times SLOWER than Python 3.8, for rather generic scientific calculations such as Fourier analysis, ODE solving and plotting. On the one hand, the "test case" is a rather complex program that calculates Wigner function of a quantum system and the result is 9 seconds when run with 3.8 and 23 seconds when run with 3.10 (very easy to reproduce: just clone this repository: https://github.com/tigran123/quantum-infodynamics and run "time bin/harmonic-oscillator-solve.sh" from the dynamics subdirectory and then edit initgauss.py and solve.py to point to python3.10 and run it again). Make sure your TMPDIR points somewhere fast. My machine is a very fast 6-core i7-6800K at 4.2GHz and 128GB RAM. The storage is also a very fast NVMe, about 3GB/s. After this try a completely different program which simulates a mathematical pendulum using PyQT (GUI) and it gives FPS:14-15 when run with 3.8 and only 11-12 when run with 3.10. Again, it is easy to reproduce if you have cloned the above repository: just go to classical-mechanics/pendulum subdirectory and run psim.py (click on the Play button in the control window and observe FPS in the plot window). Then edit psim.py to point to Python 3.10 and run it again. You would need PyQt5, matplotlib, numpy, scipy, pyFFTW for these programs to work. I realise that you would much prefer a small specific test case, but I still hope that this report is "better than nothing". I do really desire to help improve Python and will provide more information if requested. I use Python everywhere, even in Termux on Android, and am quite saddened by this degradation... With Python 3.8 I used these package versions: matplotlib 3.1.3 numpy 1.18.1 pyFFTW 0.12.0 PyQt5 5.13.2 scipy 1.4.1 With Python 3.10 I used these package versions: matplotlib 3.5.0 numpy 1.21.4 pyFFTW 0.12.0 PyQt5 5.15.6 scipy 1.7.3 Both Python 3.8 and 3.10 were compiled and installed by myself with "./configure --enable-optimizations ; make ; sudo make install". Kind regards, Tigran _______________________________________________ Python-Dev mailing list -- python-dev@python.org To unsubscribe send an email to python-dev-le...@python.org https://mail.python.org/mailman3/lists/python-dev.python.org/ Message archived at https://mail.python.org/archives/list/python-dev@python.org/message/34FP7FEG36UVBFW3ZDTL7GOQRSRBSXTQ/ Code of Conduct: http://python.org/psf/codeofconduct/
