perf: do not copy metadata for each data file in summary #2674
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Fokko
approved these changes
Nov 2, 2025
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@Anton-Tarazi This makes a lot of sense to me, thanks for digging into this and providing the patch 🙌 |
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Resolves #2673
Rationale for this change
_SnapshotProducer._summary()copies the metadata for every added / deleted DataFile. This is pretty expensive. Instead we just copy it once at the beginning of the function and use the same value each DataFile.On my data, which overwrites a few million rows at a time, I saw the time for
table.overwritego from ~20 seconds to ~6 seconds.Are these changes tested?
Yes, existing unit / integration tests
Are there any user-facing changes?
Just faster writes :)