所以,出现Waiting for table flush状态的可能情况是:有1个flush tables命令被别的语句堵住了,然后它又堵住了select语句 案例分析 Window1:CREATETABLEfoo ( idintprimarykey );Window1:STARTTRANSACTION;Window1:SELECT*FROMfoo;-- it doesn't matter that the table has no dataWindow2:DROPTABLEfoo;-- notice i...
To circumvent the locking issue on OPTIMIZE we use for the InnoDb databases the tool pt-online-schema from the package percona-toolkit, as OPTIMIZE is like an ALTER where you do no change it works fine. pt-online-schema works by doing a copy of the table to work on and keeping in sync...
Tables where information in a database continually updates, such astransactional databases, are the most likely candidates for optimization. However, optimizing large tables takes longer, and it locks tables. Locking a table for several hours may disrupt system operations. ForInnoDBengine tables, consi...
一般来说,可以查看数据库运行峰值时间的状态值Open_tables和Open_tables,用以判断是否需要增加table_cache的值,即如果Open_tables接近table_cache的时候,并且Opened_tables这个值在逐步增加,那就要考虑增加这个值的大小了。 external-locking = FALSE#MySQL选项可以避免外部锁定。True为开启。 max_allowed_packet =16M#服...
13.7.2.4 OPTIMIZE TABLE Statement OPTIMIZE[NO_WRITE_TO_BINLOG|LOCAL]TABLEtbl_name[,tbl_name]... OPTIMIZE TABLEreorganizes the physical storage of table data and associated index data, to reduce storage space and improve I/O efficiency when accessing the table. The exact changes made to each ...
table_open_cache = 2048 # Enable external file level locking. Enabled file locking will have a # negative impact on performance, so only use it in case you have # multiple database instances running on the same files (note some # restrictions still apply!) or if you use other software ...
OPTIMIZE TABLE tbl_name; Performed in-place as of MySQL 5.6.17. In-place operation is not supported for tables with FULLTEXT indexes. The operation uses the INPLACE algorithm, but ALGORITHM and LOCK syntax is not permitted. Related Percona XtraBackup 8.4 Pro: Reduce Server Locking by up to...
acquire_with_lock() : dict_table_tacquired_at : mrs::authentication::Oauth2Handler::GenericSessionData, mrs::authentication::SaslHandler::SaslSessionDataacquired_spins() : lock::Shared_spin_lockaction : CmdOption, Lock_descriptor, MY_SQL_PARSER_STYPE, PT_locking_clause, ReplaceResult, Single_...
一般来说,可以查看数据库运行峰值时间的状态值Open_tables和Open_tables,用以判断是否需要增加table_cache的值,即如果Open_tables接近table_cache的时候,并且Opened_tables这个值在逐步增加,那就要考虑增加这个值的大小了。 external-locking = FALSE # MySQL选项可以避免外部锁定。True为开启。
Fixed an issue where in special cases certain slave errors are not ignored even withslave_skip_errorsenabled. In cases when opening and locking a table failed or when field conversions failed on a server running row-based replication, the error is considered critical and the state ofslave_skip...