…’t measuring the cost of index maintenance. Transaction-id is auto-incremented, and so partitioning on transaction-id makes the insertions easy. Basically you…
Comment: InnoDB's gap locks
May 7, 2012 By 15 Comments
…(29); ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction root@localhost:test 14:38:03>insert into t values(23); ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction root@localhost:test 14:44:37>insert into t values… INNODB STATUS information as follow: —TRANSACTION 0 27638, ACTIVE 1207 sec, process no 2909, OS thread id 1100101952 inserting mysql tables in…
Comment: Emulating global transaction ID with pt-heartbeat
April 24, 2012 By 6 Comments
… that mysql does not have a way match the transactions as ‘global transactions id‘.I agree that matching logs is very tedious but…
Comment: Percona XtraDB Cluster Feature 2: Multi-Master replication
April 2, 2012 By 16 Comments
… writesets. The reason for this is keeping track of global transaction ID and caching the writesets for potential IST. This overhead can…
Post: InnoDB's gap locks
March 27, 2012 By 15 Comments
… running transaction, two identical statements get different values, because some other transaction has modified the table’s rows. For example: transaction1> START TRANSACTION…; +——+ | age | +——+ | 21 | | 25 | | 30 | +——+ Start a transaction and delete the record 25: transaction1 > START TRANSACTION; transaction1 > DELETE FROM t WHERE age=25…` trx id 72C lock_mode X locks gap before rec If you have lot of gaps locks in your transactions affecting the…
Comment: INSERT ON DUPLICATE KEY UPDATE and summary counters.
March 23, 2012 By 46 Comments
…?id=52020 Can you please explain how really locking in INSERT … ON DUPLICATE KEY UPDATE works. As I recall: Lock 1) Transaction 1 locks row for INSERT Lock 2) Transaction 2 tries to locks row for UPDATE (goes into queue) Lock 3) Transaction 1…
Comment: Instrumentation and the cost of Foreign Keys
April 19, 2012 By 9 Comments
…, someone creates an account, that account gets assigned an ID, then a transaction is created which references that account via an FK…
Comment: How FLUSH TABLES WITH READ LOCK works with Innodb Tables
March 23, 2012 By 20 Comments
…, MySQL) also provide a solution. See “START TRANSACTION WITH CONSISTENT INNODB SNAPSHOT” in https://www.facebook.com/note.php?note_id=390420710932
Post: MVCC: Transaction IDs, Log Sequence numbers and Snapshots
December 19, 2007 By 3 Comments
… you to understand MVCC a bit better. Transaction ID As the name says this is transaction identifier. It can be used by the… concurrently running transactions (not committed) is memorized. For each row more than one version can be stored, each tagged with transaction IDs which… really need to store transaction ID for the row which is so old it is visible to old running transaction anyway. So what…
Post: Emulating global transaction ID with pt-heartbeat
November 4, 2011 By 6 Comments
Global transaction IDs are being considered for a future version of MySQL. A global transaction ID lets you determine a server’s replication position… transaction ID into pt-heartbeat, the replication heartbeat tool included with Percona Toolkit. It has some of the benefits of a global transaction ID…
