[bench] Remove file prefetching from FileStream#20916
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Dandandan wants to merge 4 commits intoapache:mainfrom
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[bench] Remove file prefetching from FileStream#20916Dandandan wants to merge 4 commits intoapache:mainfrom
Dandandan wants to merge 4 commits intoapache:mainfrom
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Simplify the FileStream state machine by removing the mechanism that opens the next file in parallel while scanning the current one. Files are now opened sequentially (Scan -> Idle -> Open) instead of prefetching. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Dandandan
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run benchmarks |
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This reverts commit 38fe60a.
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Dandandan
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Mar 12, 2026
| .metrics | ||
| .clone(); | ||
| let _timer = scanning_total_metric.timer(); | ||
| self.start_next_file().transpose() |
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So this @alamb is what I was mostly talking about. It will both read the footer (what we want) but AFAIK also:
- build the pruning predicate (I think this is suboptimal, too early)
- prune row groups
- optionally load the page index
- return the stream (without driving that forward)
We should be able to do this much better with the IO / CPU separation.
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This makes sense to me 👍🏻
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Simplify the FileStream state machine by removing the mechanism that opens the next file in parallel while scanning the current one. Files are now opened sequentially (Scan -> Idle -> Open) instead of prefetching.
Which issue does this PR close?
Rationale for this change
What changes are included in this PR?
Are these changes tested?
Are there any user-facing changes?