This week Oracle will release MySQL 5.7 GA, so it’s a perfect time to do a quick review of the current state of Percona Server 5.6.26, MySQL 5.6.26 and MySQL-5.7.8 RC. We used two boxes from our benchmark lab for this: – Box 1: 16 Cores+HT (32 virt cores)/fast PCIe ssd card/RAM: 192GB – Box […]
Read MoreThank you for attending my July 22 webinar titled “Advanced Query Tuning in MySQL 5.6 and 5.7” (my slides and a replay available here). As promised here is the list of questions and my answers (thank you for your great questions). Q: Here is the explain example:
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mysql> explain extended select id, site_id from test_index_id where site_id=1 *************************** 1. row *************************** id: 1 select_type: SIMPLE table: test_index_id type: ref possible_keys: key_site_id key: key_site_id key_len: 5 ref: const rows: 1 filtered: 100.00 Extra: Using where; Using index |
why is site_id a covered index for […]
Read MoreI have heard this question quite often: “At busy times, our replicas start lagging quite frequently. We are using N schemas, so which performance boost could we expect from MySQL 5.6 parallel replication?” Here is a quick way to give you a rough estimate of the potential benefit. General idea In MySQL 5.6, parallelism is […]
Read MoreIn the past years, both MySQL 5.6, MySQL 5.7 and MariaDB 10 have been successful implementing new features. For many DBAs, the “old way” of replicating data is comfortable so taking the action to implement these new features seems like a momentous leap rather then a simple step. But perhaps it isn’t that complicated… Giuseppe […]
Read MoreIt has been a while since I have looked at InnoDB crash recovery. A lot has change in the last few years – we have serious crash recovery performance improvements in MySQL 5.5 and MySQL 5.6, we have solid state drives raising as typical high performance IO subsystem and we also have the ability to […]
Read MoreI log into a lot of different servers running MySQL and one of the first things I do is create a file in my home directory called ‘.my.cnf’ with my credentials to that local mysql instance:
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[client] user=root password=secret |
This means I don’t have to type my password in every time, nor am I tempted to include […]
Read MorePerformance Schema (P_S) has been available since MySQL 5.5, more than 4 years ago. It is still difficult to see production servers with P_S enabled, even with MySQL 5.6 where the feature is enabled by default. There have been several complaints like the overhead, that the fix is a work in progress, and the ease […]
Read MoreWith 1.28 billion active users, Facebook MySQL database engineers are active and extremely valuable contributors to the global MySQL community. So naturally they are also active participants of Percona Live MySQL conferences! And next week’s Percona Live London 2014 (Nov. 3-4) is no exception. (Register now and use the promotional code “Facebook” to save £30!) […]
Read MoreA deadlock in MySQL happens when two or more transactions mutually hold and request for locks, creating a cycle of dependencies. In a transaction system, deadlocks are a fact of life and not completely avoidable. InnoDB automatically detects transaction deadlocks, rollbacks a transaction immediately and returns an error. It uses a metric to pick the […]
Read MoreThank you to all of you who attended my webinar last week about Global Transaction IDs (GTIDs), which were introduced in MySQL 5.6 to make the reconfiguration of replication straightforward. If you missed my webinar, you can still listen to the recording and download the sides (free). We had a lot of questions during the […]
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