Grouping the whole activities table by thread every run is unusable on a large instance: on a 312 GB database it plans as a seq scan plus a 50M-row on-disk sort. Instead, walk activities in id order (flake ids are time-ordered) from a persisted cursor up to the id that corresponds to the deadline, and verify only the threads those activities belong to through the (type, context) index. Measured on that instance: 147 ms for a 50k-activity range scan, 349 ms warm / 14 s cold to verify ~700 threads. The cursor is persisted per chunk so a killed run resumes. The watermark walk keeps a cursor of its own so it cannot leave the age-based walk stranded behind the deadline. Adds the retention_cursors table. |
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| .. | ||
| benchmark.exs | ||
| config.exs | ||
| description.exs | ||
| dev.exs | ||
| docker.exs | ||
| dokku.exs | ||
| emoji.txt | ||
| prod.exs | ||
| test.exs | ||