Slow Query Accumulation Pattern
warningQueries exceeding long_query_time threshold accumulate, indicating systematic performance issues. High slow query rate signals need for query optimization, missing indexes, or resource scaling. Patterns in slow query types reveal specific optimization opportunities.
mysql.performance.slow_queries rate > 10/sec sustained for >5 minutes, with events_statements_sum_timer_wait showing high values and mysql.performance.select_scan or mysql.performance.select_full_join elevated
Enable slow query log if not already active. Query performance_schema.events_statements_summary_by_digest ordered by SUM_TIMER_WAIT to identify worst offenders. Check events_statements_sum_no_index_used and events_statements_sum_no_good_index_used for queries needing indexes. Review mysql.performance.handler_read_rnd_next for inefficient random reads. Use EXPLAIN on slow queries to identify missing indexes or poor execution plans. Monitor mysql.performance.created_tmp_disk_tables - high values indicate queries creating large temporary result sets.