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Which is the default value for InnoDB flush log at TRX commit?
The default value is 1, which helps keep InnoDB ACID Compliant. If the value of innodb_flush_log_at_trx_commit is 0, the log buffer is written out to the log file once per second and the flush to disk operation is performed on the log file, but nothing is done at a transaction commit.
When to flush the InnoDB redo log file?
When it is set to 1, the log buffer is written to the InnoDB redo log file, and a flush to disk performed after each transaction. This is required for full ACID compliance. When it is set to 2, the log buffer is written to the InnoDB redo log after each commit, but flushing takes place once a second.
How often does MySQL flush log to disk?
According to the MySQL Documentation on innodb_flush_log_at_trx_commit. If the value of innodb_flush_log_at_trx_commit is 0, the log buffer is written out to the log file once per second and the flush to disk operation is performed on the log file, but nothing is done at a transaction commit.
Is there a wait timeout for InnoDB row locks?
innodb_lock_wait_timeout applies to InnoDB row locks only. A MySQL table lock does not happen inside InnoDB and this timeout does not apply to waits for table locks.
How to reduce the time it takes to flush InnoDB?
Entering a new row or updating a row takes a little bit of time. To do 50 updates (in the format of update table set field = 1234 where id = 5678; update table set field = 912 where id = 582; …) it can take 4 or 5 seconds. How can i reduce this time? Is it worth playing with the innodb_flush_log_at_trx_commit setting?
Which is better InnoDB or MariaDB group commit?
Performance is slightly better, but a OS or power outage can cause the last second’s transactions to be lost. When it is set to 3, InnoDB emulates the older implementation of group commit, with 3 syncs to disk per group commit.
How to reduce the time it takes to update InnoDB?
To do 50 updates (in the format of update table set field = 1234 where id = 5678; update table set field = 912 where id = 582; …) it can take 4 or 5 seconds. How can i reduce this time? Is it worth playing with the innodb_flush_log_at_trx_commit setting? How can I set that setting just for certain connections/queries?