The SkySQL and MariaDB Roadshow Comes to Germany:

Stuttgart 25 January 2013, 9.00-16.00, Sodexo STEP / Engineering Park

Hamburg 1 February 2013, 9.00-16.00, Quality Ambassador Hotel

SkySQL and Monty Program are on the road with our first joint – free – roadshows in Stuttgart and Hamburg, where Monty Widenius will unveil his vision of the future of the MySQL database via MariaDB (the talk will be in English).

In addition, speakers from Codership / Galera expected, as well SkySQL experts and customer speakers.

The latest trends around the MySQL and MariaDB databases will be discussed, in cloud and high …

Database replication is one of the important part of the architecture, as it provides scalability, redudancy and backup solutions. It provides exact copy of database from master to another server (slave).  Replication can help protection against hardware failure also.

Replication lag happens very frequently in the below senarios.

• Replication on a slow network
• Replication between external network
• Replication between two different data centers.

Luckly, MySLQ has configuration variable slave_compressed_protocol which can be helpful in above senarios. This variable compress MySLQ traffic very easily. This is a dynamic parameter and can be set up on slave server.

slave_compressed_protocol = 1

Steps for setting up dynamically

1. stop slave;
2. set global slave_compressed_protocol = 1;
3. start …

In On learning InnoDB: A journey to the core, I introduced the innodb_diagrams project to document the InnoDB internals, which provides the diagrams used in this post. Later on in A quick introduction to innodb_ruby I walked through installation and a few quick demos of the innodb_space command-line tool.

The physical structure of InnoDB’s INDEX pages was described in The physical structure of InnoDB index pages. We’ll now look into how InnoDB logically structures its indexes, using some practical examples.

An aside on terminology: B+Tree, …

We have started a new series of webinars at Continuent that we call Tungsten University.  They provide education on Tungsten clustering and replication in handy one-hour chunks.  These are not sales pitches.  Our goal is to provide accessible education about setting up and operating Tungsten without any marketing fluff.

The first Tungsten University webinar entitled "Configure & provision Tungsten clusters" will take place on Thursday January 17th at 10:00 PST.  It will show you how to set up a cluster in Amazon EC2.  There will be a repeat on January 22nd at 15:00 GMT.  We usually record webinars, so you can look at them later as well. 
You do not have to be a customer to attend these webinars, …

Nagios Check For Calculating Based on Mysql Server Variables

Recently we needed to make a change for a client to one of our mysql monitoring tools so I thought it would be a good opportunity to highlight the tool and discuss some of the changes that I made.

You can access the tool on Github from our public repository here.

Before this change if you were using either the "varcomp" or "lastrun-varcomp" modes, it would only return a WARNING if your criteria for comparison were exceeded. In the new version, both WARNING and CRITICAL states can return to nagios. Here is an example: Let's say you want to alert on maximum connections, but the number of maximum connections is different for different hosts. Instead of writing distinct per/host checks, you can use this check to do a simple calculation …

Nagios Check For Calculating Based on Mysql Server Variables

Recently we needed to make a change for a client to one of our mysql monitoring tools so I thought it would be a good opportunity to highlight the tool and discuss some of the changes that I made.

You can access the tool on Github from our public repository here.

Before this change if you were using either the "varcomp" or "lastrun-varcomp" modes, it would only return a WARNING if your criteria for comparison were exceeded. In the new version, both WARNING and CRITICAL states can return to nagios. Here is an example: Let's say you want to alert on maximum connections, but the number of maximum connections is different for different hosts. Instead of writing distinct per/host checks, you can use this check to do a simple calculation …

I discovered a feature (or bug) of MySQL timestamp fields. Maybe is documented in some place what I not read yet:

When I add a new timestamp field to a table, MySQL magically adds some features to new timestamp field like a “trigger” and a default value to CURRENT_TIMESTAMP.

There is test-case script:

-- CREATING TABLE AND INSERT SOME DUMMY DATA
mysql> CREATE TABLE t(
    -> id INT NOT NULL PRIMARY KEY AUTO_INCREMENT,
    -> val VARCHAR(50)
    -> );
Query OK, 0 ROWS affected (0.15 sec)
 
mysql> INSERT INTO t (val) VALUES ("foo") ,("var");
Query OK, 2 ROWS affected (0.08 sec)
Records: 2  Duplicates: 0  Warnings: 0
 
mysql> SELECT * FROM t;
+----+------+
| id | val  |
+----+------+
|  1 | foo  |
|  2 | var  |
+----+------+
2 ROWS IN SET (0.00 sec)
 
 
-- ADDING NEW TIMESTAMP FIELD AND ADD MORE DUMMY DATA
mysql> ALTER TABLE t ADD ts_field TIMESTAMP;
Query OK, 2 ROWS affected (0.35 sec)
Records: 2  Duplicates: 0 …

There are times where you need to know exactly how much memory the mysqld server (or any other program) is using, where (i.e. for what function) it was allocated, how it got there (a backtrace, please!), and at what point in time the allocation happened.

For example; you may have noticed a sharp memory increase after executing a particular query. Or, maybe mysqld is seemingly using too much memory overall. Or again, maybe you noticed mysqld’s memory profile slowly growing overtime, indicating a possible memory bug.

Whatever the reason, there is a simple but powerful way to profile MySQL memory usage; the Massif tool from Valgrind. An excerpt from the Massif manual page (Heap memory being simply the allotted pool of memory for use by programs);

Massif tells you not only how much heap memory your program is using, it also …

In case you’ve been living under a rock for the last 5 years, the NoSQL movement has changed. There was a time when everyone – EVERYONE – was dumping on relational databases, and MySQL in particular. Nonsense like “SQL itself is inherently unscalable” routinely came out of the mouths of otherwise usually sensible people. But that’s cooled off a little bit, thank heavens. And what’s the new hotness? Well, Big Data, of course!

Percona Toolkit 2.1.8

Percona Toolkit 2.1.8 was released today and the new version comes with some pretty cool news: Beta support for MySQL 5.6 (which as you might know is also in beta).

In addition to various bug fixes, Percona Toolkit 2.1.8 also offers beta support for Percona XtraDB Cluster (PXC). Version 2.1.8 continues the trend of solid bug fix releases, and all 2.1 users are encouraged to upgrade.

You can download Percona Toolkit 2.1.8 here.  (More info on Percona Toolkit). Users who plan on running the tools on Percona XtraDB Cluster or MySQL 5.6 are advised to upgrade. …