As discussed earlier in the book, InnoDB's method for handling data change operation requires that data changes are stored in memory-based buffers and then written to log files and eventually to disk-based data tables. The process of writing to disk is resource intensive, from an I/O standpoint, and is the slowest part of the transaction commit process. As such, the performance of writing data changes to disk after a commit occurs is determined by:
Speed of your disks
RAID architecture and settings
Underlying filesystem type and behavior
The method that InnoDB uses to flush logs after a transaction is committed
InnoDB, as of MySQL 5.5, has variables to better handle high performance storage arrays so knowing the performance of your storage is a fundamental requirement in the tuning process.
We can test the performance of our I/O system with many tools. The most popular I/O specific test applications are as follows:
SysBench
Bonnie++
Fio
A typical test aims to saturate...