Uses the `Repo` field as an index during searches of the cache database. Removes unused indexes.
To measure the performance of this change, I created a synthetic test which wrote 10,000 records into the artifact cache DB. Of course, all benchmarks are lies that can't be generalized to real-world usage, but it seems clear from the magnitude of improvement that this fixes a flawed implementation, even if it's not perfect.
- Unmodified performance:
- Write: 196 records/second
- Read: 1 record/second
- With `Repo` index being used for reads, and other indexes being removed:
- Write: 347 records/second
- Read: 22,398 records/second
`Repo` is, I think, the only index that made sense to remain, with an eye on workflow run performance:
- `Key` -- can't be used for index because `findCache` searches for key *prefixes*, not equal values.
- `Version` -- isn't very distinct for different workflow runs (https://code.forgejo.org/actions/cache#cache-version)
- `Complete` - significant portion of the cache DB will be complete, making it the least selective possible index
- `UsedAt` & `CreatedAt` - only used in GC operation, so could remain, but this isn't a performance-sensitive codepath
Closes#874.
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- bug fixes
- [PR](https://code.forgejo.org/forgejo/runner/pulls/878): <!--number 878 --><!--line 0 --><!--description Zml4OiBhcnRpZmFjdCBjYWNoZSBEQiBub3QgdXNpbmcgaW5kZXhlcyBmb3Igc2VhcmNoaW5n-->fix: artifact cache DB not using indexes for searching<!--description-->
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Reviewed-on: https://code.forgejo.org/forgejo/runner/pulls/878
Reviewed-by: Michael Kriese <michael.kriese@gmx.de>
Co-authored-by: Mathieu Fenniak <mathieu@fenniak.net>
Co-committed-by: Mathieu Fenniak <mathieu@fenniak.net>
