A subset of further improvements to reduce lock contention#7105
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pcanal merged 2 commits intoroot-project:masterfrom Jan 30, 2021
Merged
A subset of further improvements to reduce lock contention#7105pcanal merged 2 commits intoroot-project:masterfrom
pcanal merged 2 commits intoroot-project:masterfrom
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On a small test with 256 threads the reduced lock contention reduces wall time from 25 minutes to 19 seconds, and increases CPU usage from 400% to 4000%.
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@phsft-bot build! |
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Build failed on ROOT-fedora31/noimt. |
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Build failed on windows10/cxx14. |
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@phsft-bot build just on windows10/cxx14 |
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pcanal
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Jan 28, 2021
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@pcanal can we merge? |
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@bendavid Thank you very much! |
bendavid
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Mar 24, 2021
This covers the changes in root-project#6857 root-project#7105 root-project#7260
eguiraud
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Mar 25, 2021
This covers the changes in root-project#6857 root-project#7105 root-project#7260
nicknagi
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Mar 30, 2021
This covers the changes in root-project#6857 root-project#7105 root-project#7260
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Further reduction in lock contention when using RDataFrame with a large number of threads and/or files, by migrating one hot spot in TBufferFile to use read-write locks instead of only write locks.
On a small test with 256 threads the reduced lock contention reduces wall time from 25 minutes to 19 seconds, and increases CPU usage from 400% to 4000%.
This PR also fixes an uninitialised variable potentially affecting the global read-write lock.