…* FROM id > 1000 FOR UPDATE twice, you expect to get the same value twice. To accomplish…to other sessions. How to troubleshoot gap locks? Is possible to detect those gap locks using SHOW ENGINE INNODB STATUS: —TRANSACTION…In the following link there is a good source of information: http://dev.mysql…
Post: Introducing new type of benchmark
February 25, 2012 By 16 Comments
…get used to that, and in fact in our benchmarks, sysbench and tpcc-mysql, the final result is also represents the throughput (transactions per second in…to your Facebook profile or Wikipedia page, you expect to get response within second or two. How we should change the benchmark to…
Post: How to debug long-running transactions in MySQL
March 8, 2011 By 6 Comments
…In MySQL 5.1 and newer with the InnoDB plugin, it’s easy to figure out which transaction…its thread ID. Match this up with the ID in SHOW PROCESSLIST, and look in … Make sure the disk isn’t getting too full. avail=$(df -m -P /root… am still stumped as to how a SELECT-only transaction can possibly have …
Post: Emulating global transaction ID with pt-heartbeat
November 4, 2011 By 6 Comments
…MySQL. A global transaction ID lets you determine a server’s replication position reliably, among other benefits. This is great when you need to… you want (or look in the documentation to see how to do it yourself), …should be running pt-heartbeat already to get a reliable indicator of actual …
Post: Modeling MySQL Capacity by Measuring Resource Consumptions
March 8, 2011 By 1 Comment
…How to get CPU consumption per query ? You can take a look at procfs for MySQL process: root@ubuntu:/var/log/mysql…TRANSACTIONS: 181243 ROLLBACK_TRANSACTIONS: 0 DENIED_CONNECTIONS: 0 LOST_CONNECTIONS: 0 ACCESS_DENIED: 0 EMPTY_QUERIES: 13099 In…QPS, 0x concurrency, ID 0x382A5F3785EB3CEE at byte …
Post: How to recover a single InnoDB table from a Full Backup
January 25, 2012 By 7 Comments
…to another. The reason is that the table definition is stored in the InnoDB shared tablespace (ibdata) and the transaction IDs…how to recover a single tablespace using stock MySQL server. First, you must meet certain prerequisites to be able to…
Post: Why audit logging with triggers in MySQL is bad for replication
September 29, 2008 By 10 Comments
…how to filter by statement. Looking through the binary logs I could see this table is actually an audit table for changes to…Transaction; Update Foo set Value=6 Where Field_Id = 51; Commit; Transaction 1 commits last. Commit; Now when these statements get…
Post: Heikki Tuuri answers to Innodb questions, Part II
November 4, 2007 By 13 Comments
…transactions per second, then you write 1000 times per second! A smart wear leveling should be able to cope with writes to…in a tolerable time? PZ: Indeed using master-master setup and switching roles is a good way to get large data manageable. MySQL…
Post: Flexviews - part 3 - improving query performance using materialized views
April 4, 2011 By 12 Comments
… to get the results you want, but more quickly. More on this later. SQL features used in … the transaction id to which you have computed them. And then confirm they contain the same results mysql> …showed how you can combine both types of views together. The complete method examples show how to create…
Post: Can MySQL temporary tables be made safe for statement-based replication?
May 26, 2008 By 8 Comments
…in ‘mysql-bin.000007′\G *************************** 1. row *************************** Log_name: mysql-bin.000007 Pos: 4 Event_type: Format_desc Server_id…to me that there’s no way to get the CREATE TEMPORARY TABLE statement to be logged inside the transaction. And when it comes to…
