Tag: InnoDB

Miscellaneous

How to Restore MySQL Logical Backup at Maximum Speed

The ability to restore MySQL logical backups is a significant part of disaster recovery procedures. It’s a last line of defense. Even if you lost all data from a production server, physical backups (data files snapshot created with an offline copy or with Percona XtraBackup) could show the same internal database structure corruption as in …

Software

Percona Server for MySQL 5.7.21-20 Is Now Available

Percona announces the GA release of Percona Server for MySQL 5.7.21-20 on February 19, 2018. Download the latest version from the Percona web site or the Percona Software Repositories. You can also run Docker containers from the images in the Docker Hub repository. Based on MySQL 5.7.21, including all the bug fixes in it, Percona Server for MySQL …

Miscellaneous

Troubleshooting MySQL Crashes Webinar: Q&A

In this blog, I will provide answers to the Q & A for the Troubleshooting MySQL Crashes webinar. First, I want to thank everybody for attending our January 25, 2018, webinar. The recording and slides for the webinar are available here. Below is the list of your questions that I was unable to answer fully during …

Miscellaneous

Fsync Performance on Storage Devices

While preparing a post on the design of ZFS based servers for use with MySQL, I stumbled on the topic of fsync call performance. The fsync call is very expensive, but it is essential to databases as it allows for durability (the “D” of the ACID acronym). Let’s first review the type of disk IO operations …

Performance

Four Ways MySQL Executes GROUP BY

In this blog post, I’ll look into four ways MySQL executes GROUP BY.  In my previous blog post, we learned that indexes or other means of finding data might not be the most expensive part of query execution. For example, MySQL GROUP BY could potentially be responsible for 90% or more of the query execution time.  …

Performance

On InnoDBs Persistent Optimizer Statistics

As I put it in recent Facebook post, one of MySQL features that I truly hate is InnoDB’s persistent statistics. I think I should clarify this statement. It’s great to have a way to save statistics in between server restarts, to have better control on the way it is estimated (even on a per table …

Clustering, Security

ClusterControl Tips & Tricks: Securing your MySQL Installation (Updated)

  Requires ClusterControl 1.2.11 or later. Applies to MySQL based clusters. During the life cycle of Database installation it is common that new user accounts are created. It is a good practice to once in a while verify that the security is up to standards. That is, there should at least not be any accounts …