[PyROOT] Fix a GIL deadlock in THx.Fit #21129
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TH1.Fit might call into Python functions, which would require the GIL to be held. If TH1.Fit holds it, though, the process deadlocks. Here, the GIL is released before TH1.Fit, which runs fully in C++ anyway. Fix root-project#21080.
This saves startup times and collects TH1 tests in one place.
The timeout of the test is reduced because the deadlock would otherwise show only after 1500s.
hageboeck
requested review from
bellenot,
guitargeek and
vepadulano
as code owners
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Nice, and compute intense functions like these is exactly when the GIL should be released to enable Python multithreading. Did you check the Pythonization also works for TH1-derived classes? |
We checked in the interpreter: >>> import ROOT
>>> ROOT.TH2.Fit.__release_gil__
True |
Test Results 22 files 22 suites 3d 13h 0m 33s ⏱️ For more details on these failures, see this check. Results for commit 290f4ed. ♻️ This comment has been updated with latest results. |
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I've taken a look at the MacOS failures. There seems to be some other kind of interference on that platform for two different types of functions that release the GIL, namely the distributed RDataFrame execution and now TH1.Fit. Needs investigation |
3 participants
TH1.Fit might call into Python functions, which would require the GIL to
be held. If TH1.Fit holds it, though, the process deadlocks.
Here, the GIL is released before TH1.Fit, which runs fully in C++
anyway.
A test was added with a 30s timeout. It completes in about 1s, unless the
GIL deadlock is maintained.
Fix #21080.