PG15: Prefetch cleanup: index bulkdelete prefetching #246
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MMeent
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- Prefetch the pages in index vacuum's sequential scans Implemented in NBTREE, GIST and SP-GIST. BRIN does not have a 2nd phase of vacuum, and both GIN and HASH clean up their indexes in a non-seqscan fashion: GIN scans the btree from left to right, and HASH only scans the initial buckets sequentially.
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knizhnik
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MMeent
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- Prefetch the pages in index vacuum's sequential scans Implemented in NBTREE, GIST and SP-GIST. BRIN does not have a 2nd phase of vacuum, and both GIN and HASH clean up their indexes in a non-seqscan fashion: GIN scans the btree from left to right, and HASH only scans the initial buckets sequentially.
MMeent
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May 11, 2023
- Prefetch the pages in index vacuum's sequential scans Implemented in NBTREE, GIST and SP-GIST. BRIN does not have a 2nd phase of vacuum, and both GIN and HASH clean up their indexes in a non-seqscan fashion: GIN scans the btree from left to right, and HASH only scans the initial buckets sequentially.
tristan957
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Aug 10, 2023
- Prefetch the pages in index vacuum's sequential scans Implemented in NBTREE, GIST and SP-GIST. BRIN does not have a 2nd phase of vacuum, and both GIN and HASH clean up their indexes in a non-seqscan fashion: GIN scans the btree from left to right, and HASH only scans the initial buckets sequentially.
tristan957
pushed a commit
that referenced
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Nov 8, 2023
- Prefetch the pages in index vacuum's sequential scans Implemented in NBTREE, GIST and SP-GIST. BRIN does not have a 2nd phase of vacuum, and both GIN and HASH clean up their indexes in a non-seqscan fashion: GIN scans the btree from left to right, and HASH only scans the initial buckets sequentially.
tristan957
pushed a commit
that referenced
this pull request
Nov 8, 2023
- Prefetch the pages in index vacuum's sequential scans Implemented in NBTREE, GIST and SP-GIST. BRIN does not have a 2nd phase of vacuum, and both GIN and HASH clean up their indexes in a non-seqscan fashion: GIN scans the btree from left to right, and HASH only scans the initial buckets sequentially.
tristan957
pushed a commit
that referenced
this pull request
Nov 8, 2023
- Prefetch the pages in index vacuum's sequential scans Implemented in NBTREE, GIST and SP-GIST. BRIN does not have a 2nd phase of vacuum, and both GIN and HASH clean up their indexes in a non-seqscan fashion: GIN scans the btree from left to right, and HASH only scans the initial buckets sequentially.
tristan957
pushed a commit
that referenced
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Feb 5, 2024
- Prefetch the pages in index vacuum's sequential scans Implemented in NBTREE, GIST and SP-GIST. BRIN does not have a 2nd phase of vacuum, and both GIN and HASH clean up their indexes in a non-seqscan fashion: GIN scans the btree from left to right, and HASH only scans the initial buckets sequentially.
tristan957
pushed a commit
that referenced
this pull request
Feb 5, 2024
- Prefetch the pages in index vacuum's sequential scans Implemented in NBTREE, GIST and SP-GIST. BRIN does not have a 2nd phase of vacuum, and both GIN and HASH clean up their indexes in a non-seqscan fashion: GIN scans the btree from left to right, and HASH only scans the initial buckets sequentially.
tristan957
pushed a commit
that referenced
this pull request
Feb 6, 2024
- Prefetch the pages in index vacuum's sequential scans Implemented in NBTREE, GIST and SP-GIST. BRIN does not have a 2nd phase of vacuum, and both GIN and HASH clean up their indexes in a non-seqscan fashion: GIN scans the btree from left to right, and HASH only scans the initial buckets sequentially.
tristan957
pushed a commit
that referenced
this pull request
May 10, 2024
- Prefetch the pages in index vacuum's sequential scans Implemented in NBTREE, GIST and SP-GIST. BRIN does not have a 2nd phase of vacuum, and both GIN and HASH clean up their indexes in a non-seqscan fashion: GIN scans the btree from left to right, and HASH only scans the initial buckets sequentially.
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Prefetch the pages in index vacuum's sequential scans.
This is implemented most efficiently in NBTREE, GIST and SP-GIST due to their effectively sequential vacuum scans with minimal backtracking.
HASH indexes benefit from prefetching as well, as each bucket can be prefetched. The existence of overflow pages makes this more difficult than we'd want, though...
BRIN does not implement a 2nd phase of vacuum, so we do not need to prefetch pages.
GIN cleans up its indexes in a non-seqscan fashion: it scans the 2 btrees from left to right, so prefetching would be very non-trivial to implement. Any prefetching would necessitate significant code changes that I'm not yet comfortable with.