… are used by one user to lock records for edit/update, so the transaction is not interrupted until the transaction is…
Comment: Load management Techniques for MySQL
May 10, 2012 By 3 Comments
… only need to implement a generic Gearman Worker to take update transactions to apply and pace MySQL transactions to the real… all batch job processing and use Gearman Workers to apply updates to this dedicated master, using pacing in the Gearman Workers… dbs in the cluster. Maybe Percona could implement built-in update pacing using Gearman and Percona provided generic worker. You might…
Comment: Multi Column indexes vs Index Merge
May 8, 2012 By 30 Comments
… high perfomance in select queries, but worsen perfomance in Insert, Update and Delete queries. Is it true? And if is it…??? too many indexes and high performance select or high perfomance update with few indexes??? how balance it??? I wait for a…
Comment: InnoDB's gap locks
May 7, 2012 By 15 Comments
… tried your example “the affect gap locks to SELECT … FOR UPDATE ” on my server ,and my results are as follow: Transaction1…(s) MySQL thread id 31929, query id 484616 localhost root update insert into t values(33) ——- TRX HAS BEEN WAITING 34…
Comment: Percona Server 5.5.23-25.3 released!
May 16, 2012 By 2 Comments
Any update on when an Ubuntu Precise (12.04 LTS) repo will be available?
Comment: How to change innodb_log_file_size safely
May 2, 2012 By 14 Comments
It’s quite likely that something simple is happening, like you’re updating the wrong .cnf file. Check the error log for more clues.
Comment: How to change innodb_log_file_size safely
May 2, 2012 By 14 Comments
… other forums (i think that’s frowned up) but will update with any resolution. I can’t figure out what i…
Post: Give feedback on a pt-online-schema-change update
March 14, 2012 By 2 Comments
I am writing a specification for updating pt-online-schema-change. The outline of the changes I …
Post: InnoDB's gap locks
March 27, 2012 By 15 Comments
…> START TRANSACTION; transaction1> SELECT * FROM t WHERE i > 20 FOR UPDATE; +——+ | i | +——+ | 21 | | 25 | | 30 | +——+ transaction2> START TRANSACTION; transaction2> INSERT INTO… a SELECT. They only occur if you do UPDATE or DELETE or SELECT FOR UPDATE. InnoDB provides REPEATABLE READ for read-only…
Comment: INSERT ON DUPLICATE KEY UPDATE and summary counters.
March 23, 2012 By 46 Comments
… please explain how really locking in INSERT … ON DUPLICATE KEY UPDATE works. As I recall: Lock 1) Transaction 1 locks row… INSERT Lock 2) Transaction 2 tries to locks row for UPDATE (goes into queue) Lock 3) Transaction 1 tries to locks row for UPDATE (goes into queue) It is reasonable not to release Lock…
