…looks something like this: SELECT * FROM table WHERE deleted = 0 AND group_id IN (62715996…_wait_event,rw_lock_s_lock_spin,pfs_rw_lock_s_lock_fu nc…::exec,mysql_sel ect,handle_select,execute_sqlcom_select,mysql_execute_command,mysql_… worse in this workload and innodb_adaptive_hash_index_partitions=16 …
Post: InnoDB thread concurrency
June 5, 2006 By 4 Comments
…delete_row; At start of each of these methods InnoDB checks count of already entered threads, and if this count is over innodb…Innodb tables…innodb_thread_concurrency. This is why innodb_commit_concurrency variable was added in MySQL 5.0 innodb…
Post: Heikki Tuuri Innodb answers - Part I
October 26, 2007 By 19 Comments
…delete a lot of scattered rows you may not see a “free space” in Innodb tablespace to grow significantly. Q6: Does Innodb…InnoDB normally does not lock the ‘gaps’, and it does not lock…MySQL 5.1 Q15: How frequently does Innodb fuzzy checkpointing is activated HT: InnoDB…
Post: MySQL Server Variables - SQL layer or Storage Engine specific.
June 8, 2006 By 14 Comments
…some tables in MyISAM format in “mysql” database. Plus HEAP/MEMORY tables are used for temporary tables… – when to delete binary logs from master. It does not affect Innodb and other…table locks or if LOCK TABLES are used. So in practice this option is used for MyISAM and MEMORY tables. max_write_lock…
Post: MySQL Backup tools used by Percona Remote DBA for MySQL
March 13, 2013 By 8 Comments
… can happen? Someone runs UPDATE or DELETE and forgets the where clause …A table (or entire schema) was dropped accidentally Your InnoDB table was corrupt and mysql …lock times here when non-transactional tables are used Almost no locking, if not using myisam tables Built in compression Each table…
Post: MySQL 5.6: Improvements in the Nutshell
January 27, 2013 By 16 Comments
…MySQL…Innodb Memory Fragmentation – Reduced Locking for Partitioned tables – Reduced Contention for LOCK_open – Support for multiple table…
Post: Announcing Percona XtraDB Cluster 5.5.29-23.7.1
January 30, 2013 By 8 Comments
…fixed #1081389 (Alex Yurchenko). Running FLUSH TABLES WITH READ LOCK when slave applier needed to…delete for a table with foreign key constraint. Bug fixed #1078346 (Seppo Jaakola). When variable innodb…-XtraDB-Cluster-client would conflict with mysql and mysql-server packages. Bug fixed #1087506 (…
Post: Percona Server 5.5.10 (Release Candidate)
April 4, 2011 By 4 Comments
…innodb_row_lock_numbers was renamed to innodb_current_row_locks. (Yasufumi Kinoshita) Old system variable innodb_enable_unsafe_group_commit was deleted. The existing MySQL variable innodb…
Comment: Database problems in MySQL/PHP Applications
August 11, 2006 By 13 Comments
…With some > exception however. For example Innodb tables do internal full table > lock if auto_increment is used so…Read more in my > Why MySQL Could be slow with Large Tables article. Deciding whether or not… add processing time to inserts, updates, and deletes but there are other benefits. Also – if…
Comment: InnoDB's gap locks
May 7, 2012 By 15 Comments
…) root@localhost:test 14:35:22>delete from t where i=25; Query …INNODB STATUS information as follow: —TRANSACTION 0 27638, ACTIVE 1207 sec, process no 2909, OS thread id 1100101952 inserting mysql tables in use 1, locked 1 LOCK WAIT 2 lock struct(s), heap size 1216, 1 row lock(s) MySQL…
