…],but it came out my insert still be blocked. The SHOW ENGINE INNODB STATUS information as follow: —TRANSACTION 0 27638, ACTIVE 1207 sec, process…
Post: InnoDB's gap locks
March 27, 2012 By 15 Comments
… gap locks? Is possible to detect those gap locks using SHOW ENGINE INNODB STATUS: —TRANSACTION 72C, ACTIVE 755 sec 4 lock struct(s), heap… need to create locks to prevent that from happening. 2- innodb_locks_unsafe_for_binlog = 1. Disables the gap locks except… information: http://dev.mysql.com/doc/refman/5.1/en/innodb-locks-set.html. Conclusion MySQL uses REPEATABLE READ as the…
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 3 Comments
…. row *************************** SESSION_ID: 7234 TABLE_SCHEMA: test TABLE_NAME: my ENGINE: InnoDB NAME: #sql516_1c42_2 TABLE_ROWS: 0 AVG_ROW_LENGTH…. row *************************** SESSION_ID: 7231 TABLE_SCHEMA: test TABLE_NAME: z ENGINE: InnoDB NAME: #sql516_1c3f_0 TABLE_ROWS: 0 AVG_ROW_LENGTH… Innodb has allocated. In fact this is often one of the first things I do as it is least intrusive. Run SHOW ENGINE INNODB STATUS…
Comment: InnoDB thread concurrency
March 19, 2012 By 4 Comments
…, can i ask you quesiton? i issue the command ‘show engine innodb status‘, is shows there are 10 io threads(4 are read, 4 are… (write thread) but i found that the value of the innodb_thread_concurrency is 8. so, what is wrong with this…
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
…numbers for Innodb_buffer_pool_read_ahead which shows that the access pattern was sequential and hence InnoDB … be seen by the numbers reported for the status counter Innodb_rows_read. While MySQL 5.6 is…single call to the storage engine and the counters Handler_read_key and Innodb_rows_read are …
Post: Index Condition Pushdown in MySQL 5.6 and MariaDB 5.5 and its performance impact
March 12, 2012 By 12 Comments
I have been working with Peter in preparation for the talk comparing the optimizer enhancements in MySQL 5.6 and MariaDB 5.5. We are taking a look at and benchmarking optimizer enhancements one by one. So in the same way this blog post is aimed at a new optimizer enhancement Index Condition …
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 2 Comments
… batched together and sent to the storage engine. The storage engine then uses the MRR interface (which I …. Now let’s take a look at the status counters. Counter Name MySQL 5.5 MySQL 5….the high numbers of Innodb_buffer_pool_read_ahead when the buffers are sized appropriately, which shows that the …
Post: A quest for the full InnoDB status
October 31, 2008 By 4 Comments
… the status file on disk even if you do not specify innodb-status-file option. The file is actually used for every SHOW ENGINE InnoDB STATUS call, so whenever someone runs the command, InnoDB writes the…
Post: Different flavors of InnoDB flushing
January 13, 2011 By 9 Comments
… list. You can see a tracking of these lists in SHOW ENGINE INNODB STATUS: … Pending writes: LRU 0, flush list 129, single page 0… flushing comes from the LRU list? You could periodically check SHOW ENGINE INNODB STATUS, and see something like Pending writes: LRU N, flush list…
Post: How to calculate a good InnoDB log file size
November 21, 2008 By 33 Comments
…grep sequence PAGER set to ‘grep sequence’ mysql> show engine innodb status\G select sleep(60); show engine innodb status\G Log sequence number 84 3836410803 1 row…5.0 and newer, you can just watch Innodb_os_log_written from SHOW GLOBAL STATUS, too.) mysql> select (3838334638 – 3836410803) / 1024 / …
