Read Index Operations Slowing Down Linearizable Reads
warninglatencyUpdated Feb 23, 2024
High etcd_server_read_index_slow count or failures indicate that read index operations (required for linearizable reads) are timing out, degrading read performance and consistency guarantees.
How to detect:
Monitor etcd_server_read_index_slow and etcd_server_read_index_failed counters. Correlate with quorum communication latency and leader stability. Check logs for read index timeout messages.
Recommended action:
Investigate network latency between cluster members as read index requires quorum communication. Check leader stability and disk performance. Consider using serializable reads for non-critical queries to bypass read index overhead. Verify no network partitions are intermittently affecting quorum.