search

cockroachdb / cockroach

CockroachDB — the cloud native, distributed SQL database designed for high availability, effortless scale, and control over data placement.
https://www.cockroachlabs.com
Other
29.86k stars 3.77k forks source link

admission: lower physical cluster replication to background work priority #122136

Open kvoli opened 5 months ago

kvoli commented 5 months ago

Is your feature request related to a problem? Please describe. PCR currently uses normal admission control priority, meaning it won't be subject to replication AC. We saw that this can lead to uncontrolled IO overload, as follower writes bypass AC:

image

Describe the solution you'd like

Lower the admission control work priority of PCR to background here:

https://github.com/cockroachdb/cockroach/blob/935d796608663c74b726ad42659cd91aa502d11b/pkg/ccl/streamingccl/streamingest/stream_ingestion_processor.go#L992-L995

Jira issue: CRDB-37721

sumeerbhola commented 4 months ago

see https://cockroachlabs.slack.com/archives/C01SRKWGHG8/p1712653528148439 for internal discussion