7.20 Myisam Configuration Metrics

Lists the Myisam configuration metrics and provides a brief description of each.

Table 7.20 Myisam Configuration Metrics

Name	Description
Concurrent Insert	Permits INSERT and SELECT statements to run concurrently for MyISAM tables that have no free blocks in the middle of the data file.
Delay Key Write	Delayed key writing causes key buffers not to be flushed between writes for MyISAM tables.
Keep Files On Create Enabled	Whether to overwrite MyISAM MYD/MYI files or return an error if no DATA DIRECTORY / INDEX DIRECTORY option is set, and the files already exist.
Key Buffer Size	The size of the buffer used for MyISAM index blocks.
Key Cache Age Threshold	Controls the demotion of buffers from the hot sublist of a MyISAM key cache to the warm sublist.
Key Cache Block Size	The size in bytes of blocks in the MyISAM key cache.
Key Cache Division Limit	The division point between the hot and warm sublists of the MyISAM key cache buffer list.
Myisam Data Pointer Size	The default pointer size, in bytes, to be used by CREATE TABLE for MyISAM tables when no MAX_ROWS option is specified.
Myisam Max Sort File Size	The maximum size of the temporary file that MySQL is permitted to use while re-creating a MyISAM index (during REPAIR TABLE, ALTER TABLE, or LOAD DATA INFILE).
Myisam Mmap Size	The maximum amount of memory to use for memory mapping compressed MyISAM files.
Myisam Recover Options	Sets the MyISAM storage engine recovery mode.
Myisam Repair Threads	If this value is greater than 1, MyISAM table indexes are created in parallel (each index in its own thread) during the Repair by sorting process.
Myisam Sort Buffer Size	The size of the buffer that is allocated when sorting MyISAM indexes during a REPAIR TABLE or when creating indexes with CREATE INDEX or ALTER TABLE.
Myisam Stats Method	How the server treats NULL values when collecting statistics about the distribution of index values for MyISAM tables.
Myisam Use Mmap Enabled	Use memory mapping for reading and writing MyISAM tables.
Skip External Locking Enabled	Do not use external locking (system locking) to lock MyISAMtable files.