Use faster method to determine open file count #59429
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QDir is VERY slow for this calculation, because all related QDir methods require construction of the entry list upfront, which involves a bunch of extra work in calculating file attributes In a simple benchtest of trying to open 1000s of files using the ogr provider ~25% of the time was spent in calculating open file count. Afterwards this drops to <0.5%.
nyalldawson
added
Optimization
🪟 Windows buildsDownload Windows builds of this PR for testing. 🪟 Windows Qt6 buildsDownload Windows Qt6 builds of this PR for testing. |
rouault
approved these changes
Nov 13, 2024
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QDir is VERY slow for this calculation, because all related QDir methods require construction of the entry list upfront, which involves a bunch of extra work in calculating file attributes
In a simple benchtest of trying to open 1000s of files using the ogr provider ~25% of the time was spent in calculating open file count. Afterwards this drops to <0.5%.