MySQL status explained in detail

State name Scope detailed explanation Aborted_clientsglobal the number of connections that were interrupted because the client did not shut down the connection properly due to a client termination Aborted_connectsglobal attempts to connect to the MySQL server failed connections Binlog_ Cache_disk_useglobal the number of transactions using the temporary binary log cache but exceeding the Binlog_cache_size value and using temporary files to hold statements in the transaction binlog_cache_ Useglobal the number of transactions Bytes_receivedboth received from all clients using the temporary binary log cache. Bytes_sentboth the number of bytes sent to all clients. com*  number of database operations compressionsession the number of connections between the client and the server is not enabled Connectionsglobal attempts to connect to the MySQL server (regardless of success) Created_tmp_ Disk_tablesboth the number of temporary tables that are automatically created on the hard disk when the server executes the statement created_tmp_filesglobalmysqld the number of temporary files that have been created Created_tmp_ Tablesboth the number of temporary tables in memory that are automatically created when the statement is executed by the server. If the created_tmp_disk_tables is larger, you may want to increase the tmp_table_size value so that the temp   table is based on memory and not on the hard disk Delayed_errorsglobal insert  Delayed the number of rows that were written incorrectly (possibly Duplicate key). The number of insert delayed processor threads used by the Delayed_insert_threadsglobal. Delayed_writesglobal the number of flush statements executed by the number of insert delayed rows Flush_commandsglobal written. Handler_commitboth the number of internal commit statements handler_deleteboth the number of times the row was deleted from the table. The Handler_discoverbothmysql server can ask Ndb cluster if the storage engine knows the table of a particular name. This is called discovery. Handler_discover describes the number of times that this method was discovered. Handler_preparebotha counter for the preparE phase of two-phase commit operations. The number of times the first read in the Handler_read_firstboth index. If it is high, it is recommended that the server is performing a large number of full-index scans; For example, Select col1 from foo, assuming Col1 has an index. Handler_read_keyboth the number of requests to read a row according to the key. If it is high, the index of the query and table is correct. Handler_read_nextboth reads the number of requests for the next line in key order. This value increases if you query an index column with a range constraint or if an index scan is performed. Handler_read_prevboth the number of requests to read the previous line in key order. This reading method is mainly used to optimize order by ... desc. Handler_read_rndboth the number of requests to read a row based on a fixed position. This value is higher if you are executing a large number of queries and need to sort the results. You may have used a large number of queries that require MySQL to scan the entire table or your connection did not use the keys correctly. Handler_read_rnd_nextboth the number of requests to read the next line in the data file. If you are doing a large number of table scans, this value is higher. It is usually indicated that your table index is incorrect or the query being written does not take advantage of the index. Handler_rollbackboth the number of internal rollback statements. Handler_savepointboth the number of requests to place a savepoint in a storage engine. Handler_savepoint_rollbackboth the requirement of a storage engine to roll back to a savepoint number. Handler_updateboth the number of requests to update a row within a table. Handler_writeboth the number of requests to insert a row within a table. Innodb_buffer_pool_pages_dataglobal contains the number of pages (dirty or clean) of the data. Innodb_buffer_pool_pages_dirtyglobal the current number of dirty pages. Innodb_buffer_pool_pages_flushedglobal the number of buffer pool pages required to be emptied innodb_buffer_pool_pages_freeglobal empty pages. Innodb_buffer_pool_pages_latchedglobal the number of pages locked in the INNODB buffer pool. This is the number of pages that are currently being read or written or cannot be emptied or deleted for other reasons. Innodb_buffer_poOl_pages_miscglobal busy pages because they have been assigned precedence for administration, such as row locking or applicable hash indexes. This value can also be calculated as Innodb_buffer_pool_pages_total - innodb_buffer_pool_pages_free - innodb_buffer_ Pool_pages_data. Innodb_buffer_pool_pages_totalglobal Total buffer pool size (pages). Innodb_buffer_pool_read_ahead_rndglobalinnodb the number of "random" read-aheads initialized. Occurs when the query scans a large part of a table in a random order. Innodb_buffer_pool_read_ahead_seqglobalinnodb the number of sequential read-aheads initialized. Occurs when InnoDB performs a sequential full-table scan. Innodb_buffer_pool_read_requestsglobalinnodb the number of logical read requests that have been completed. The Innodb_buffer_pool_readsglobal cannot satisfy the logical read count in a buffer pool that Innodb must read in a single page. Innodb_buffer_pool_wait_freeglobal General, write to the INNODB buffer pool through the background. However, if you need to read or create a page, and there is no clean page available, it also needs to wait for the page to empty first. The counter counts the waiting instance. If the buffer pool size is already set appropriately, the value should be small. Innodb_buffer_pool_write_requestsglobal the number of writes to the INNODB buffer pool. The number of Innodb_data_fsyncsglobalfsync () operands. Innodb_data_pending_fsyncsglobal the number of Fsync () operands currently pending. Innodb_data_pending_readsglobal the current pending reading. Innodb_data_pending_writesglobal the current number of pending writes. Innodb_data_readglobal the number of data (bytes) that have been read to this point. Innodb_data_readsglobal The total number of data reads. Innodb_data_writesglobal The total number of data writes. Innodb_data_writtenglobal The amount of data (bytes) that has been written to this point. Innodb_dblwr_Pages_writtenglobal the number of double write operations that have been performed innodb_dblwr_writesglobal a double write operation has already been written on the page Innodb_log_waitsglobal we have to wait for the time since the log buffer is too small, We must wait for the number of Innodb_log_write_requestsglobal log write requests to be emptied before proceeding. Innodb_log_writesglobal the number of physical writes to the log file. Innodb_os_log_fsyncsglobal the number of Fsync () writes completed to the log file. Innodb_os_log_pending_fsyncsglobal the number of pending log file Fsync () operations. Innodb_os_log_pending_writesglobal pending log file writes Innodb_os_log_writtenglobal the number of bytes written to the log file. Innodb_page_sizeglobal compiled Innodb page size (default 16KB). Many values are counted in pages, and the size of the page is easily converted to bytes. Innodb_pages_createdglobal the number of pages created. The number of pages read by Innodb_pages_readglobal. Number of pages written by Innodb_pages_writtenglobal. Innodb_row_lock_current_waitsglobal the number of rows currently waiting to be locked. Innodb_row_lock_timeglobal the total time, in milliseconds, that the row lock takes. Innodb_row_lock_time_avgglobal the average time, in milliseconds, that the row is locked. Innodb_row_lock_time_maxglobal the maximum time, in milliseconds, that a row is locked. Innodb_row_lock_waitsglobal the number of times a row lock must wait. Innodb_rows_deletedglobal the number of rows deleted from the Innodb table. Innodb_rows_insertedglobal the number of rows inserted into the Innodb table. Innodb_rows_readglobal the number of rows read from the Innodb table. The number of rows updated in the Innodb_rows_updatedglobalinnodb table. The number of data blocks in the Key_blocks_not_flushedglobal key cache that have been changed but have not yet been emptied to the hard disk. The number of unused blocks in the Key_blocks_unusedglobal key cache. You can use theValue to determine how many keys are used to cache the number of blocks used within the Key_blocks_usedglobal key cache. The value is a high-level line marker that shows how many blocks have been used at the same time. Key_read_requestsglobal the number of requests from the cache to read the data block of the key. Key_readsglobal the number of times the key's data block was read from the hard disk. If the key_reads is large, the Key_buffer_size value may be too small. You can calculate the cache loss rate with key_reads/key_read_requests. Key_write_requestsglobal the number of requests to write the key's data block to the cache. Key_writesglobal the number of times the physical write operation of the data block to which the key was written to the hard disk. Last_query_costsession the total cost of the last compiled query computed with the query optimizer. Used to compare the cost of different query scenarios for the same query. The default value of 0 indicates that the query has not been compiled. The   default value is 0. Last_query_cost has a session scope. Max_used_connectionsglobal the maximum number of connections that have been used at the same time since the server started. NDB* NDB cluster-dependent not_flushed_delayed_rowsglobal number of rows waiting to be written to the Insert delay queue.  open_filesglobal the number of open files. Open_streamsglobal the number of open streams (primarily for logging). The number of Open_table_definitionsglobal cached. frm files Open_tablesboth The number of currently open tables. The number of open opened_filesglobal files. Other types of files, such as sockets or pipes, are not included.   does not include files that the storage engine uses to do its own internal functions. Opened_table_definitionsboth the number of the. frm files that have been cached Opened_tablesboth the number of tables that have been opened. If the opened_tables larger,table_cache  value may be too small. Prepared_stmt_countglobal the number of current preprocessing statements.   (maximum number is System variable:  max_prepared_stmt_count) qcache_free_blocksglobal the number of free memory blocks in the query cache. Qcache_free_memoryglobal The amount of free memory used to query the cache. Qcache_hitsglObal the number of times the query cache was accessed. Qcache_insertsglobal the number of queries added to the cache. Qcache_lowmem_prunesglobal the number of queries that are removed from the cache because of less memory. Qcache_not_cachedglobal number of non-cached queries (not cacheable, or because Query_cache_type setpoint is not cached). Qcache_queries_in_cacheglobal the number of queries registered in the cache. Qcache_total_blocksglobal the total number of blocks in the query cache. The number of requests that the Queriesboth server executes, including requests in the stored procedure. Questionsboth the number of queries that have been sent to the server. Rpl_statusglobal Failed Secure replication status (not yet used). Select_full_joinboth the number of joins that do not use an index. If the value is not 0, you should carefully examine the index of the table select_full_range_joinboth the number of joins in the referenced table using the range search. Select_rangeboth the number of joins that use a range in the first table. The general situation is not a critical issue, even if the value is quite large. Select_range_checkboth the number of joins without a key value that are checked for key values after each row of data. If it is not 0, you should carefully check the index of the table. Select_scanboth the number of joins that perform a full scan of the first table. Slave_heartbeat_periodglobal Replication heartbeat interval Slave_open_temp_tablesglobal The number of temporary tables opened from the server Slave_received_ Heartbeatsglobal Slave_retried_transactionsglobal The number of thread attempts from the server since the start of the server heartbeat Slave_ Runningglobal If the server is a slave server that is connected to the primary server, the value is on. Slow_launch_threadsboth the number of threads that have created longer than slow_launch_time seconds. Slow_queriesboth the number of queries that have been queried for more than long_query_time seconds. Sort_merge_passesboth the number of merges that the sorting algorithm has performed. If the value of this variable is large, you should consider increasing the value of the sort_buffer_size system variable. Sort_rangeboth the number of sorts that are executed within the range. Sort_rowsboth the number of rows that have been sorted. Sort_scAnboth the number of sorting completed by the scan table. Ssl* ssl the number of times the lock on the table that the associated Table_locks_immediateglobal immediately obtains. Table_locks_waitedglobal the number of times a table lock cannot be obtained immediately. If the value is high and there is a performance problem, you should first refine the query and then split the table or use replication. Threads_cachedglobal the number of threads within the thread cache. Threads_connectedglobal the number of connections currently open. Threads_createdglobal creates the number of threads used to process the connection. If the threads_created is larger, you may want to increase the thread_cache_size value. The method of calculating the cache access rate is threads_created/connections. Threads_runningglobal the number of active (non-sleep-state) threads. The time, in seconds, that the Uptimeglobal server has been running. Uptime_since_flush_statusglobal the last time the flush status  was used (in seconds).

MySQL status explained in detail