InnoDB System Variables • innodb_lru_scan_depth Command-Line Format --innodb-lru-scan-depth=# System Variable innodb_lru_scan_depth Scope Global Dynamic Yes SET_VAR  Hint Applies No Type Integer Default Value 1024 Minimum Value 100 Maximum Value (64-bit platforms) 2**64-1 Maximum Value (32-bit platforms) 2**32-1 A parameter that influences the algorithms and heuristics for the flush operation for the  InnoDB  buffer pool. Primarily of interest to performance experts tuning I/O-intensive workloads. It specifies, per buffer pool instance, how far down the buffer pool LRU page list the page cleaner thread scans looking for dirty pages to flush. This is a background operation performed once per second. A setting smaller than the default is generally suitable for most workloads. A value that is much higher than necessary may impact performance. Only consider increasing the value if you have spare I/O capacity under a typical workload. Conversely, if a write-intensive workload saturates your I/O capacity, decrease the value, especially in the case of a large buffer pool. When tuning  innodb_lru_scan_depth , start with a low value and configure the setting upward with the goal of rarely seeing zero free pages. Also, consider adjusting  innodb_lru_scan_depth when changing the number of buffer pool instances, since  innodb_lru_scan_depth  * innodb_buffer_pool_instances  defines the amount of work performed by the page cleaner thread each second. For related information, see Section 15.8.3.5, “Configuring Buffer Pool Flushing” . For general I/O tuning advice, see Section 8.5.8, “Optimizing InnoDB Disk I/O” . • innodb_max_dirty_pages_pct Command-Line Format --innodb-max-dirty-pages-pct=# System Variable innodb_max_dirty_pages_pct Scope Global Dynamic Yes SET_VAR  Hint Applies No Type Numeric Default Value 90 Minimum Value 0 3263