[DEPRECATED] Promscale is a unified metric and trace observability backend for Prometheus, Jaeger and OpenTelemetry built on PostgreSQL and TimescaleDB.
We have seen instances in which compresses chunks are missing statistics. Autovacuum ignores tables that are missing statistics. Analyzing these tables does not help since we rarely modify chunks after they are compressed. Therefore, these chunks are ignored until they pass the vacuum_freeze_max_age. This can be bad for performance. So, the vacuum engine makes a second pass looking for these chunks and vacuums them. We only use one worker for these.
Description
We have seen instances in which compresses chunks are missing statistics. Autovacuum ignores tables that are missing statistics. Analyzing these tables does not help since we rarely modify chunks after they are compressed. Therefore, these chunks are ignored until they pass the vacuum_freeze_max_age. This can be bad for performance. So, the vacuum engine makes a second pass looking for these chunks and vacuums them. We only use one worker for these.
See also: https://github.com/timescale/promscale_extension/pull/595
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