What are MySQL performance schema and sys schema?

Performance Schema:
• Runtime performance monitoring
• Low-level instrumentation data
• Memory, I/O, lock statistics

Sys Schema:
• User-friendly views of Performance Schema
• Pre-built queries for common tasks
• Easier performance analysis

Example:
SELECT * FROM sys.schema_table_statistics;
SELECT * FROM performance_schema.events_waits_summary_global_by_event_name;