Prepared Statement Limit Reached
warningNumber of prepared statements approaching max_prepared_stmt_count limit. When limit reached, new prepared statements are rejected, causing application errors. Often indicates prepared statement leaks in application code.
mysql.performance.prepared_stmt_count / mysql.performance.max_prepared_stmt_count > 0.85, with mysql.performance.prepared_stmt_count steadily increasing
Query performance_schema.prepared_statements_instances to identify prepared statements. If count continuously increases, application is not deallocating statements (DEALLOCATE PREPARE). Review application connection lifecycle - statements should be prepared once per connection and reused. Check for statement preparation in loops without deallocation. Increase max_prepared_stmt_count if legitimate high usage, but investigate potential leaks first. Each prepared statement consumes memory, so unbounded growth indicates a resource leak. Monitor mysql.prepared_statements for execution patterns.