Code run with cProfile performance regression in 3.11

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See this discussion on Discourse.

We could speed up cProfile a few ways. I'll try to work on a few PRs. We first need to find out why cProfile is so slow. I'm not sure if we can backport fixes. Though a 1.6x slowdown seems pretty significant.

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An update: I can reproduce the results that OP posted for his application. That is:

3.10 with cProfile:
Time Elapsed: 3.6727186999924015

3.11 with cProfile:
Time Elapsed: 6.189334200011217

Without cProfile, there's a 10-20% speedup over 3.10.

python main.py -n 500

3.10 without cProfile:
Time Elapsed: 15.240909200001624

3.11 without cProfile:
Time Elapsed: 12.682664599997224

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Another update: between python 3.10 and 3.11, test_cprofile didn't slow down at all (in fact, it sped up slightly). That likely indicates that cprofile itself didn't slow down, it's likely the impact of tracing code went up instead.

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This was mostly fixed in #93516. The next release (3.11b4) will have all the fixes included.

3.10 profiler.py
Time Elapsed: 2.1907681000002412

3.11b4 profiler.py
Time Elapsed: 2.4747707999995328