MySQL 4.1 introduces a new
on a per-key cache basis. This variable specifies the size of
the block buffers for a key cache. It is intended to enable
tuning of the performance of I/O operations for index files.
The best performance for I/O operations is achieved when the size of read buffers is equal to the size of the native operating system I/O buffers. But setting the size of key nodes equal to the size of the I/O buffer does not always ensure the best overall performance. When reading the big leaf nodes, the server pulls in a lot of unnecessary data, effectively preventing reading other leaf nodes.
To control the size of blocks in the
index file of
MyISAM tables, use the
--myisam-block-size option at