MySQL の総メモリ利用量を算出するSQL の SQL の場合、MySQL のバージョンによっては利用できないため、以下のような SQL で代用できます。
select @@GLOBAL.KEY_BUFFER_SIZE + @@GLOBAL.INNODB_BUFFER_POOL_SIZE + @@GLOBAL.INNODB_LOG_BUFFER_SIZE + @@GLOBAL.INNODB_ADDITIONAL_MEM_POOL_SIZE + @@GLOBAL.NET_BUFFER_LENGTH as GLOBAL_BUFFER_SIZE, @@GLOBAL.SORT_BUFFER_SIZE + @@GLOBAL.MYISAM_SORT_BUFFER_SIZE + @@GLOBAL.READ_BUFFER_SIZE + @@GLOBAL.JOIN_BUFFER_SIZE + @@GLOBAL.READ_RND_BUFFER_SIZE as THREAD_BUFFER_SIZE, @@GLOBAL.KEY_BUFFER_SIZE + @@GLOBAL.INNODB_BUFFER_POOL_SIZE + @@GLOBAL.INNODB_LOG_BUFFER_SIZE + @@GLOBAL.INNODB_ADDITIONAL_MEM_POOL_SIZE + @@GLOBAL.NET_BUFFER_LENGTH + (@@GLOBAL.SORT_BUFFER_SIZE + @@GLOBAL.MYISAM_SORT_BUFFER_SIZE + @@GLOBAL.READ_BUFFER_SIZE + @@GLOBAL.JOIN_BUFFER_SIZE + @@GLOBAL.READ_RND_BUFFER_SIZE) * @@GLOBAL.MAX_CONNECTIONS AS TOTAL_MEMORY_SIZE, (@@GLOBAL.KEY_BUFFER_SIZE + @@GLOBAL.INNODB_BUFFER_POOL_SIZE + @@GLOBAL.INNODB_LOG_BUFFER_SIZE + @@GLOBAL.INNODB_ADDITIONAL_MEM_POOL_SIZE + @@GLOBAL.NET_BUFFER_LENGTH + (@@GLOBAL.SORT_BUFFER_SIZE + @@GLOBAL.MYISAM_SORT_BUFFER_SIZE + @@GLOBAL.READ_BUFFER_SIZE + @@GLOBAL.JOIN_BUFFER_SIZE + @@GLOBAL.READ_RND_BUFFER_SIZE) * @@GLOBAL.MAX_CONNECTIONS)/1024 AS TOTAL_MEMORY_SIZE_kb, (@@GLOBAL.KEY_BUFFER_SIZE + @@GLOBAL.INNODB_BUFFER_POOL_SIZE + @@GLOBAL.INNODB_LOG_BUFFER_SIZE + @@GLOBAL.INNODB_ADDITIONAL_MEM_POOL_SIZE + @@GLOBAL.NET_BUFFER_LENGTH + (@@GLOBAL.SORT_BUFFER_SIZE + @@GLOBAL.MYISAM_SORT_BUFFER_SIZE + @@GLOBAL.READ_BUFFER_SIZE + @@GLOBAL.JOIN_BUFFER_SIZE + @@GLOBAL.READ_RND_BUFFER_SIZE) * @@GLOBAL.MAX_CONNECTIONS)/1024/1024 AS TOTAL_MEMORY_SIZE_mb, (@@GLOBAL.KEY_BUFFER_SIZE + @@GLOBAL.INNODB_BUFFER_POOL_SIZE + @@GLOBAL.INNODB_LOG_BUFFER_SIZE + @@GLOBAL.INNODB_ADDITIONAL_MEM_POOL_SIZE + @@GLOBAL.NET_BUFFER_LENGTH + (@@GLOBAL.SORT_BUFFER_SIZE + @@GLOBAL.MYISAM_SORT_BUFFER_SIZE + @@GLOBAL.READ_BUFFER_SIZE + @@GLOBAL.JOIN_BUFFER_SIZE + @@GLOBAL.READ_RND_BUFFER_SIZE) * @@GLOBAL.MAX_CONNECTIONS)/1024/1024/1024 AS TOTAL_MEMORY_SIZE_gb \G
