pageserver: do big reads to fetch slru segment #11029
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Problem Each page of the slru segment is fetched individually when it's loaded on demand. Summary of Changes Use `Timeline::get_vectored` to fetch 16 at a time.
problame
approved these changes
Feb 27, 2025
| let mut segment = BytesMut::with_capacity(n_blocks as usize * BLCKSZ as usize); | ||
| for blkno in 0..n_blocks { | ||
| let block = self | ||
| .get_slru_page_at_lsn(kind, segno, blkno, lsn, ctx) |
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The only remaining user of get_slru_page_at_lsn is map_all_timestamps, which is also invoked in a "for-each-block" loop.
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| let keyspace = KeySpace::single( | ||
| slru_block_to_key(kind, segno, 0)..slru_block_to_key(kind, segno, n_blocks), | ||
| ); |
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random note: we should probably use smallvec in KeySpace
| slru_block_to_key(kind, segno, 0)..slru_block_to_key(kind, segno, n_blocks), | ||
| ); | ||
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| let partitions = keyspace.partition( |
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nit: name partition sounds like keyspace partitioning. batch, maybe?
7744 tests run: 7366 passed, 0 failed, 378 skipped (full report)Flaky tests (2)Postgres 17
Code coverage* (full report)
* collected from Rust tests only The comment gets automatically updated with the latest test results
f82edc6 at 2025-02-27T20:10:01.084Z :recycle: |
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Problem
Each page of the slru segment is fetched individually when it's loaded on demand.
Summary of Changes
Use
Timeline::get_vectoredto fetch 16 at a time.TODO: does this stuff have any test coverage?