… How frequently does Innodb fuzzy checkpointing is activated HT: InnoDB flushes about 128 dirty pages per flush…. only way to get good performance is to set innodb_flush_log_at_trx_commit=2, that is, to flush the log to the disk…had serve regressions in 5.0 because of group commit being broken. Most …
Post: How InnoDB handles REDO logging
February 3, 2011 By 18 Comments
…innodb_flush_log_at_trx_commit = 0 /* Write log buffer to log about once a second and flush */ innodb_flush_log_at_trx_commit = 1 /* Write log buffer to log and flush to disk */ innodb_flush_log_at_trx_commit = 2 /* Write log buffer to log and flush…
Post: MySQL 4 to MySQL 5 Upgrade performance regressions
June 6, 2007 By 8 Comments
…to 5.0 upgrade notes ? ? Furthermore if there were no good ideas how to make XA to work with group commit…to have innodb_flush_logs_at_trx_commit=1 so transactions are truly durable. You have to have log-bin enabled to get replication or point in time recovery, but at… set your RAID cache policy to “…
Post: MySQL should have dynamic durability settings
April 8, 2008 By 4 Comments
…Innodb tables MySQL has innodb_flush_log_at_trx_commit variable which defines how durable your transactions are. If you have high durability requirements you set it to 1 and log…
Post: How innodb_open_files affects performance
November 18, 2009 By 4 Comments
…Innodb data dictionary the operation is slower than MyISAM tables. Though the difference can be related to the size of set… time and about 260sec second time (with innodb_flush_log_at_trx_commit=0) go giving 550 and 380 updates/sec … in the list. I guess Heikki knows how to implement LRU in the…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
…how much IO your log file requires. Note depending on your innodb_flush_log_at_trx_commit value your log writes may be more or less expensive. If innodb_flush_logs_at_trx_commit=2 log…
Post: Optimizing InnoDB for creating 30,000 tables (and nothing else)
December 22, 2011 By 5 Comments
…set some InnoDB options! I’m going to try the obvious first: innodb-flush-method, sync-frm and innodb-flush-log-at-trx-commit. There is an undocumented option for innodb-flush…
Post: Testing the Group Commit Fix
July 13, 2011 By 13 Comments
…to summarize: the fix improves performance substantially when both innodb_flush_log_at_trx_commit=1 and sync_binlog=1 options are set…Commit Fix in an upcoming Percona Server release. It is also interesting to see how Flash cards will handle innodb_flush_log_at_trx_commit…
Post: InnoDB thread concurrency
June 5, 2006 By 4 Comments
…innodb_thread_concurrency setting. if you have innodb_flush_logs_at_trx_commit=1 and do not have battery backed up cache on your log volume you might want to play with larger values such as 20. If innodb_log_flush_at_trx_commit=0…
Comment: When is it a time to upgrade memory ?
December 9, 2009 By 11 Comments
…to the “innodb_flush_log_at_trx_commit=2″ into the config file. The “innodb_buffer_pool_size” is set to…log file size to about 25% of the buffer pool size innodb_log_group_home_dir = /mnt/log_mysql innodb_log_file_size=1G innodb_log_buffer_size=64M innodb_flush_log_at_trx_commit…
