MySQL variables related to system performance

The original MySQL variables related to system performance are excerpted from: forge. mysql. comwikiServerVariablesMemory-RelatedVariables memory variables TheseservervariablescontroltheamountofmemoryallocatedtothevariousbuffersandcacheswithinMySQL.

MySQL Variables Related to system performance Source: http://forge.mysql.com/wiki/ServerVariables Memory-Related variables memory Variables These server variables control the amount of Memory allocated to the varous buffers and caches within MySQL.

MySQL variables related to system performance

Extracted from: http://forge.mysql.com/wiki/ServerVariables

Memory-Related Variables
Memory Variables

These server variables control the amount of memory allocated to the varous buffers and caches within MySQL.
The following server variables control the total memory allocated to various buffers or caches by MySQL.

join_buffer_size
(Per session) Controls the amount of memory allocated to perform joins on tables that have no keys which can be used to perform a condition filter. Allocated for each table joined without necessary filter conditions
(Session variable) controls the total number of memories allocated when no index table is connected. It can be used as a condition filter. Allocate each table in the connection without necessary filtering conditions.

key_buffer_size
(GLOBAL) (MyISAM-only) Controls the amount of memory allocated to the MyISAM index key cache
(Global variables) (For MyISAM tables only) the total memory allocated to the MyISAM index cache.

innodb_buffer_pool_size
(GLOBAL) (InnoDB-only) Controls the amount of memory allocated to the InnoDB cache containing both clustered data and secondary index pages
(Global variable) (For Innodb only) controls the total memory allocated to Innodb cache including cluster data and secondary index pages.

innodb_additional_mem_pool_size
(GLOBAL) (InnoDB-only) Controls the amount of memory allocated to the buffer storing the InnoDB internal data dictionary
(Global variable) (For Innodb only) controls the buffer allocated to sort Innodb internal data dictionaries.

innodb_log_buffer_size
(GLOBAL) (InnoDB-only) Controls the amount of memory allocated to the buffer storing InnoDB write-ahead log entries
(Global variable) (For Innodb only) controls the buffer allocated to write logs in advance to Innodb Storage.

query_cache_size
(GLOBAL) Controls the amount of memory allocated to the Query Cache
(Global variable) controls the total memory allocated to the query cache.

read_buffer_size
(Per session) Controls the amount of memory allocated to the connecting thread in order to process a table scan
(Session variable) controls the total number of connection thread memory allocated to the processing scan table.

read_rnd_buffer_size
(Per session) Controls the amount of memory allocated to the buffer used to read previously sorted results
(Session variable) controls the total number of buffers allocated to read the results of the current sorting.

sort_buffer_size
(Per session) Controls the amount memory allocated to the buffer used to sort result sets before returning the set to the calling client
(Session variable) controls the total number of buffers required to sort the result set before returning the result to the called client.

thread_stack
(Per session) Controls the default stack memory allocated for each connecting thread
(Session variable) controls the total number of default stack memory allocated to each connection thread.

tmp_table_size
(GLOBAL) Controls the maximum memory to allocate to a temporary table before MySQL converts it into an on-disk MyISAM table
(Global variable) controls the maximum memory size required by MySQL to convert a temporary table to a MyISAM Table stored on disk.

Thread-Related Variables
Thread-related variables

thread_cache_size
(GLOBAL) Determines the number of thread connection objects that MySQL keeps in a cache to mitigate resource creation costs
(Global variable) determine the number of connection threads that MySQL maintains in the cache, which can reduce the system resources required to create a connection.