Details
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Bug
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Resolution: Done
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P2: Important
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None
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5.12.4, 5.13.0
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31012df705c37503be00f0ddc2c323e73fd28067 (qt/qtbase/5.13)
Description
Looks like the fix for QTBUG-54275 ( " QGraphicsScene::update(): Keep the list of updatedRects() unique" 1d09b0d1b28eaea17069f7359956640f31ea79c6 https://codereview.qt-project.org/c/qt/qtbase/+/241098 ) causes update() call to get very slow due to it scanning the whole list. qFuzzyCompare and especially qAbs is showing up quite high in a profiler.
With attached minimal example, press the button and it will freeze for a while.
On my system, Qt 5.11.3 completes in 9ms, but Qt 5.12.4 takes over 6 seconds.
Attachments
For Gerrit Dashboard: QTBUG-77952 | ||||||
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# | Subject | Branch | Project | Status | CR | V |
272462,13 | Fix QGraphicsScene::update() performance | 5.13 | qt/qtbase | Status: MERGED | +2 | 0 |
273834,5 | Add a benchmark for QGraphicsScene::update() | 5.13 | qt/qtbase | Status: ABANDONED | -1 | 0 |