Hi Kristian, On 21/02/2013 13:31, Kristian Nielsen wrote: >> I tried setting SERIALIZABLE isolation globally and confirmed that >> (much) more deadlocks happened. But unfortunately "Duplicate entry" >> error still happens. >> >> @@GLOBAL.tx_isolation: SERIALIZABLE >> @@tx_isolation: SERIALIZABLE >> @@innodb_locks_unsafe_for_binlog: 1 > > I don't know. > > I am not sure what the semantics is for setting innodb_locks_unsafe_for_binlog > at the same time as SERIALIZABLE. They seem kind of contradictory to me. > > Do you still get the deadlocks if you use SERIALIZABLE without > innodb_locks_unsafe_for_binlog?
Sorry for late reply. Yes still deadlocks happen often with using SERIALIZABLE without innodb_locks_unsafe_for_binlog. Considering our use cases, it seems that using REPEATABLE-READ with innodb_locks_unsafe_for_binlog is faster than other options we tried, even though our application should handle "Duplicate entry" well to retry transactions, because this way has much less deadlocks. > By the way, you do not need to set SERIALIZABLE globally. Why not set it only > for that particular kind of transaction? Yes I know. I set it globally only because it was the easiest way without modifying the application at all... Regards, -- Kazuhiko Shiozaki, Nexedi SA Senior Consultant Nexedi: Consulting and Development of Free / Open Source Software http://www.nexedi.com/ ERP5: Full Featured High End Open Source ERP http://www.erp5.com/ _______________________________________________ Mailing list: https://launchpad.net/~maria-developers Post to : maria-developers@lists.launchpad.net Unsubscribe : https://launchpad.net/~maria-developers More help : https://help.launchpad.net/ListHelp
