…sec 633 lock struct(s), heap size 96696, 218786 row lock(s), undo log entries 1 MySQL thread …gap locks for range scans. select * from some_table where id > 100 FOR UPDATE; The above update will create a gap lock… view for the transaction lasts only as long as each statement execution. As a result,…
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November 20, 2009 By 2 Comments
…gap locking“. Gap locking effectively involves locking…locks. A normal SELECT does not lock at all. In addition, an UPDATE or DELETE only acquires a temporary row-lock. This lock…MySQL calls the engine “init” method on startup it is holding the global LOCK_plugin lock…
Post: Avoiding auto-increment holes on InnoDB with INSERT IGNORE
November 29, 2011 By 8 Comments
…MySQL 5.1.22 InnoDB used a method to access that counter values called “Traditional”. This one uses a special table lock…lock at the same time, so we lose concurrency and performance. The problems are even worse with long… INSERT … ON DUPLICATE KEY UPDATE produce gaps on the auto_increment column….
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July 17, 2006 By 40 Comments
…mysql tables in use 1, locked 1 LOCK WAIT 3 lock struct(s), heap size 320 MySQL thread id 30898, query id 100626 localhost root Updating update… trx id 0 42313620 lock_mode X locks rec but not gap Record lock, heap no 5 … – dirty pages which were not accessed long time, flush list – old pages which …
Post: INSERT INTO ... SELECT Performance with Innodb tables.
July 12, 2006 By 22 Comments
… by small bulks, which do not cause long enough locks to cause the problems. To complete…updating or deleting mysql tables in use 1, locked 1 LOCK WAIT 3 lock struct(s), heap size 320, undo log entries 1 MySQL…` trx id 0 42304626 lock_mode X locks rec but not gap waiting Record lock, heap no 180 …
