[ntuple] Merger: avoid resealing if not needed#20112
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silverweed merged 2 commits intoroot-project:masterfrom Dec 4, 2025
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[ntuple] Merger: avoid resealing if not needed#20112silverweed merged 2 commits intoroot-project:masterfrom
silverweed merged 2 commits intoroot-project:masterfrom
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Test Results 22 files 22 suites 3d 20h 32m 11s ⏱️ For more details on these failures, see this check. Results for commit 40620a61. ♻️ This comment has been updated with latest results. |
jblomer
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Nice!
I think the codimd write-up should be submitted as a doc PR.
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Currently we either "fast merge" the page (i.e. we copy it as-is to the
destination) or we reseal it if fast merging is not possible.
There is a middle ground where we can avoid resealing if only the page
compression differs but not the on-disk encoding.
We were not currently leveraging this and doing the extra work of
resealing the pages in all cases where just recompression could be done.
With this PR we introduce this middle ground case ("L2 merging", aka
"recompress merging") which skips the resealing (thus the re-encoding)
of the pages whenever possible.
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hahnjo
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Currently we either "fast merge" the page (i.e. we copy it as-is to the destination) or we reseal it if fast merging is not possible (which happens where the compression or the on-disk encoding don't match).
There is a middle ground where we can avoid resealing if only the page compression differs but not the on-disk encoding.
We were not currently leveraging this and doing the extra work of resealing the pages in all cases where just recompression could be done.
With this PR we introduce this middle ground case ("L2 merging", aka "recompress merging") which skips the resealing (thus the re-encoding) of the pages whenever possible.
(see here for the L2 terminology)
Checklist: