You are here

Shinguz's blog

Do not underestimate performance impacts of swapping on NUMA database systems

Taxonomy upgrade extras: 

If your MariaDB or MySQL database system is swapping it can have a significant impact on your database query performance! Further it can also slow down your database shutdown and thus influence the whole reboot of your machine. This is especially painful if you have only short maintenance windows or if you do not want to spend the whole night with operation tasks.

Dropped Tables with FromDual Backup Manager

Taxonomy upgrade extras: 

Some applications have the bad behaviour to CREATE or DROP tables while our FromDual Backup Manager (bman) backup is running.

This leads to the following bman error message:

FromDual Ops Center for MariaDB and MySQL 0.9.1 has been released

Taxonomy upgrade extras: 

FromDual has the pleasure to announce the release of the new version 0.9.1 of its popular FromDual Ops Center for MariaDB and MySQL focmm.

The FromDual Ops Center for MariaDB and MySQL (focmm) helps DBA's and System Administrators to manage MariaDB and MySQL database farms. Ops Center makes DBA and Admins life easier!

FromDual Ops Center for MariaDB and MySQL 0.9 has been released

Taxonomy upgrade extras: 

Caution: We have introduced an evil bug which prohibits installation of focmm. Sorry! Somehow it did pass our QA. To fix this bug update file lib/Upgrade.inc on Line 1965 as follows:

- $sql = sprintf("REPLACE INTO `focmm_configuration` (`key`, `value`) VALUES ('%s', '%s'), ('%s', '%s'), ('%s', '%s')"
+ $sql = sprintf("REPLACE INTO `focmm_configuration` (`key`, `value`) VALUES ('%s', '%s'), ('%s', '%s')"

In the meanwhile we prepare a new release.

MariaDB Prepared Statements, Transactions and Multi-Row Inserts

Last week at the MariaDB/MySQL Developer Training we had one participant asking some tricky questions I did not know the answer by heart.

Also MariaDB documentation was not too verbose (here and here).

So time to do some experiments:

Uptime of a MariaDB Galera Cluster

Taxonomy upgrade extras: 

A while ago somebody on Google Groups asked for the Uptime of a Galera Cluster. The answer is easy... Wait, no! Not so easy... The uptime of a Galera Node is easy (or not?). But Uptime of the whole Galera Cluster?

My answer then was: "Grep the error log." My answer now is still: "Grep the error log." But slightly different:

Linux system calls of MySQL process

We had the problem today that a MySQL Galera Cluster node with the multi-tenancy pattern caused a lot of system time (sy 75%, load average about 30 (you really must read this article by Brendan Gregg, it is w

MariaDB and MySQL Database Consolidation

Taxonomy upgrade extras: 

We see at various customers the request for consolidating their MariaDB and MySQL infrastructure. The advantage of such a measure is clear in the first step: Saving costs! And this request comes typically from managers. But what we unfortunately see rarely is to question this request from the IT engineering perspective. Because it comes, as anything in life, with some "costs". So, saving costs with consolidation on one side comes with "costs" for operation complexity on the other side.

FromDual Performance Monitor for MariaDB and MySQL 1.0.2 has been released

FromDual has the pleasure to announce the release of the new version 1.0.2 of its popular Database Performance Monitor for MariaDB, MySQL, Galera Cluster and Percona Server fpmmm.

The new FromDual Performance Monitor for MariaDB and MySQL (fpmmm) can be downloaded from here. How to install and use fpmmm is documented in the fpmmm Installation Guide.

MariaDB and MySQL consulting by plane

Since January 2019 FromDual tries to contribute actively a little bit against global warming too.

The best for the climate would be to NOT travel to the customer at all! For this cases we have our FromDual remote-DBA services for MariaDB and MySQL.

MySQL Enterprise Backup Support Matrix

MySQL Enterprise Backup (MEB) is a bit limited related to support of older MySQL versions. So you should consider the following release matrix:

MariaDB/MySQL Environment MyEnv 2.0.2 has been released

FromDual has the pleasure to announce the release of the new version 2.0.2 of its popular MariaDB, Galera Cluster and MySQL multi-instance environment MyEnv.

The new MyEnv can be downloaded here. How to install MyEnv is described in the MyEnv Installation Guide.

Using tmux for MariaDB database support and surveillance

Taxonomy upgrade extras: 

See also our older article: Using screen for support and/or surveillance.

First simple steps

The command tmux starts a tmux server and opens a new session with a (pseudo) terminal:

shell> tmux

tmux1.png

To leave a tmux session again just type Ctrl+d inside your tmux session or:

To NULL, or not to NULL, that is the question!

As we already stated in earlier articles in this blog [1 and 2] it is a good idea to use NULL values properly in MariaDB and MySQL.

UNDO logs in InnoDB system tablespace ibdata1

Taxonomy upgrade extras: 

We see sometimes at customers that they have very big InnoDB system tablespace files (ibdata1) although they have set innodb_file_per_table = 1.

So we want to know what else is stored in the InnoDB system tablespace file ibdata1 to see what we can do against this unexpected growth.

First let us check the size of the ibdata1 file:

MariaDB indexing of NULL values

Taxonomy upgrade extras: 

In the recent MariaDB DBA advanced training class the question came up if MariaDB can make use of an index when searching for NULL values... And to be honest I was not sure any more. So instead of reading boring documentation I did some little tests:

Search for NULL

First I started with a little test data set. Some of you might already know it:

MariaDB/MySQL Schulungstermine 2019

Jetzt sind auch noch die letzten MariaDB und MySQL Schulungstermine für 2019 festgelegt und veröffentlicht.

Mit unseren drei Schulungspartnern in Essen, Köln und Berlin bietet FromDual zur Zeit insgesamt 12 öffentliche Schulungen zum Thema MariaDB und MySQL an.

Es sind dies:

MariaDB/MySQL Environment MyEnv 2.0.1 has been released

FromDual has the pleasure to announce the release of the new version 2.0.1 of its popular MariaDB, Galera Cluster and MySQL multi-instance environment MyEnv.

The new MyEnv can be downloaded here. How to install MyEnv is described in the MyEnv Installation Guide.

Schulung MariaDB/MySQL für Fortgeschrittene vom 12.-16. 11. in Köln

Taxonomy upgrade extras: 

In unserer FromDual Schulung MariaDB/MySQL für Fortgeschrittene vom 12. bis 16. November in Köln hat es zur Zeit noch 3 Plätze frei.

Anmelden können Sie sich direkt bei unserem Schulungspartner GfU in Köln.

Cool new features in FromDual Backup and Recovery Manager 2.0.0

A while ago we released our FromDual Backup and Recovery Manager (brman) 2.0.0 for MariaDB and MySQL. So what are the new cool features of this new release?

First of all brman 2.0.0 is compatible with MariaDB 10.3 and MySQL 8.0:

Select Hello World FromDual with MariaDB PL/SQL

MariaDB 10.3 was released GA a few weeks ago. One of the features which interests me most is the MariaDB Oracle PL/SQL compatibility mode.

So its time to try it out now...

Special MySQL and MariaDB trainings 2018 in English

Due to a strong customer demand FromDual offers 2018 two extra MySQL/MariaDB trainings with its Training partner The Linuxhotel in Essen (Germany). Those trainings are in English.

  • MariaDB Performance Tuning on 5 and 6 September 2018 (2 days).
  • Advanced MySQL/MariaDB training on 26 to 30 November 2018 (5 days).

More information about the contents of the trainings can be found at Advanced MySQL and MariaDB training.

MySQL sys Schema in MariaDB 10.2

Taxonomy upgrade extras: 

MySQL has introduced the PERFORMANCE_SCHEMA (P_S) in MySQL 5.5 and made it really usable in MySQL 5.6 and added some enhancements in MySQL 5.7 and 8.0.

Pages

Subscribe to RSS - Shinguz's blog