In the InnoDB plugin, a new variable was added named innodb_io_capacity, which controls the maximum number of I/O operations per second that InnoDB will perform (which includes the flushing rate of dirty pages as well as the insert buffer (ibuf) batch size).
First off, let me just say this is a welcome addition (an addition provided by the Google Team, fwiw).
However, before this was configurable, the internal hard-coded value for this was 100. But when this became configurable, the default was increased to 200.
For many systems, this is not an issue (i.e., the overall system can perform 200 IOPS).
However, there are still many disks (which is often the [Read more...]