About year ago Peter wrote about redundant indexes and mentioned sometimes it is good to leave two indexes, even one is first part of another. I’m speaking about BTREE indexes, for example, KEY (A), and KEY (A,B). From SQL point of view KEY(A) is not needed, as for queries like WHERE A=5 the index (A,B) […]
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Percona is glad to announce the new release of Percona XtraDB Cluster 5.6 on March 5th 2015. Binaries are available from downloads area or from our software repositories. Based on Percona Server 5.6.22-72.0 including all the bug fixes in it, Galera Replicator 3.9, and on Codership wsrep API 25.8, Percona XtraDB Cluster 5.6.22-25.8 is now […]
If you use Percona Server 5.5 and you have configured it to use multiple buffer pool instances than sooner or later you’ll see the following lines on the server’s error log and chances are you’ll be worried about them:
InnoDB: detected cycle in LRU for buffer pool 5, skipping to next buffer pool.
InnoDB: detected cycle in LRU for buffer pool 3, skipping to next buffer pool.
InnoDB: detected cycle in LRU for buffer pool 7, skipping to next buffer pool.
Worry not as this is mostly harmless. It’s becoming a February tradition for me (Fernando) […]
MySQL meets NoSQL with JSON UDF I recently got back from FOSDEM, in Brussels, Belgium. While I was there I got to see a great talk by Sveta Smirnova, about her MySQL 5.7 Labs release JSON UDF functions. It is important to note that while the UDF come in a 5.7 release it is absolutely […]
Percona is pleased to announce the availability of Percona Toolkit 2.2.13. Released January 26, 2015. Percona Toolkit is a collection of advanced command-line tools to perform a variety of MySQL server and system tasks that are too difficult or complex for DBAs to perform manually. Percona Toolkit, like all Percona software, is free and open source. This release is […]
Mydumper is known as the faster (much faster) mysqldump alternative. So, if you take a logical backup you will choose Mydumper instead of mysqldump. But what about the restore? Well, who needs to restore a logical backup? It takes ages! Even with Myloader. But this could change just a bit if we are able to take […]
A few days ago I wrote about MySQL performance implications of InnoDB isolation modes and I touched briefly upon the bizarre performance regression I found with InnoDB handling a large amount of versions for a single row. Today I wanted to look a bit deeper into the problem, which I also filed as a bug. First […]
Over the past few months I’ve written a couple of posts about dangerous debt of InnoDB Transactional History and about the fact MVCC can be the cause of severe MySQL performance issues. In this post I will cover a related topic – InnoDB Transaction Isolation Modes, their relationship with MVCC (multi-version concurrency control) and how […]
Today we announced the full conference sessions schedule for April’s Percona Live MySQL Conference & Expo 2015 and this year’s event, once again at the Hyatt Regency Santa Clara and Santa Clara Convention Center, looks to be the biggest yet with networking and learning opportunities for MySQL professionals and enthusiasts at all levels. Conference sessions […]
Percona is glad to announce the release of Percona Server 5.6.22-71.0 on January 12, 2015. Download the latest version from the Percona web site or from the Percona Software Repositories. Based on MySQL 5.6.22, including all the bug fixes in it, Percona Server 5.6.22-71.0 is the current GA release in the Percona Server 5.6 series. Percona Server is open-source […]