grafana_database_backend_wait_time_seconds

Rising pending compaction tasks silently degrade read performance by forcing queries to scan more SSTables. This storage debt accumulates invisibly until read latency spikes occur.

Grafana instances using Cassandra as a backend can experience silent performance degradation when JMX metrics (compaction tasks, heap usage, GC pauses) are not collected. Without JMX visibility, operators miss early warnings of heap exhaustion, compaction backlog, or GC thrashing that manifest as sudden dashboard failures.