Ahoi, I made three proposals for Percona Live. (Even I know being
a lonely (sniff) freelancer with no backup). At least I'm
for sure an early adopter about the three topics I submitted and
know for sure what I'm talking about *g*
Even being Puppet certified. Ansible is my love. Never been that
fast in doing automation \o/
This is a tutorial about Docker and Galera/MySQL.
With the release of 10.1.8, MariaDB takes a next step. MariaDB 10.1 is now considered a stable release.
MariaDB 10.1 has a couple of main themes:
During the last few years there have been many request for more security features in MariaDB. Actually it’s a trend in general. Since open source software is getting more attractive all the time, more functionality is wanted in areas where proprietary software typically has been leading. This is especially true for databases. In addition data privacy is a very hot topic.
The big new thing in security for MariaDB 10.1 is a complete data at rest encryption solution. The encryption that now is in use originates from Google’s encryption patch. It has now been migrated into MariaDB 10.1. The …
[Read more]State Snapshot Transfer (SST) at a glance
PXC uses a protocol called State Snapshot Transfer to provision a node joining an existing cluster with all the data it needs to synchronize. This is analogous to cloning a slave in asynchronous replication: you take a full backup of one node and copy it to the new one, while tracking the replication position of the backup.
PXC automates this process using scriptable SST methods. The most common of these methods is the xtrabackup-v2 method which is the default in PXC 5.6. Xtrabackup generally is more favored over other SST methods because it is non-blocking on the Donor node (the node contributing the backup).
The basic flow of this method is:
Sun of database technologies is shining through the cloud technology. Oracle, SQL Server, MySQL and various other databases are bringing forth some nifty offerings and this Log Buffer Edition covers some of them.
Oracle:
In my previous post, I used incremental backups in Percona XtraBackup as a method for rebuilding a Percona XtraDB Cluster (PXC) node without triggering an actual SST. Practically this reproduces the SST steps, but it can be handy if you already had backups available to use.
In this post, I want to present another methodology for this that also uses a full backup, but instead of incrementals uses any binary logs that the cluster may be producing.
Binary logs on PXC
Binary logs are not strictly needed in PXC for replication, but …
[Read more]Beware the SST
In Percona XtraDB Cluster (PXC) I often run across users who are fearful of SSTs on their clusters. I’ve always maintained that if you can’t cope with a SST, PXC may not be right for you, but that doesn’t change the fact that SSTs with multiple Terabytes of data can be quite costly.
SST, by current definition, is a full backup of a Donor to Joiner. The most popular method is Percona XtraBackup, so we’re talking about a donor node that must:
The MariaDB project is pleased to announce the immediate availability of MariaDB Galera Cluster 10.0.20 and MariaDB Galera Cluster 5.5.44. These are Stable (GA) releases.
Download MariaDB Galera Cluster 10.0.20
Release Notes Changelog What is MariaDB Galera Cluster?
[Read more]Some applications have a heavy write workload on a few records – for instance when incrementing a global counter: this is called a write hotspot. Because you cannot update the same row simultaneously from multiple threads, this can lead to performance degradation. When using Percona XtraDB Cluster (PXC), some users try to solve this specific issue by writing on multiple nodes at the same time. Good idea or bad idea? Read on!
Simultaneous writes on a standalone InnoDB server
Say you have these 3 transactions being run simultaneously (id is the primary key of the table):
# T1 UPDATE t SET ... WHERE id = 100 # T2 UPDATE t SET ... WHERE id = 100 # T3 UPDATE t SET ... WHERE id = 101
All transactions will require a row lock on the record they want to modify. So T3 can commit at the same time than T1 and/or T2, because it will …
[Read more]It seems these days if anyone knows anything about tuning InnoDB, it’s that you MUST tune your innodb_buffer_pool_size to 80% of your physical memory. This is such prolific tuning advice, it seems engrained in many a DBA’s mind. The MySQL manual to this day refers to this rule, so who can blame the DBA? The question is: does it makes sense?
What uses the memory on your server?
Before we question such advice, let’s consider what can take up RAM in a typical MySQL server in their broad categories. This list isn’t necessarily complete, but I think it outlines the large areas a MySQL server could consume memory.
I often talk with people who are very interested in the features of Percona XtraDB Cluster (PXC) such as synchronous and parallel replication, multi-node writing and high availability. However some get confused when operating a real PXC cluster because they do not fully realize the implications of these features. So here is a fun way to test your PXC knowledge: try to solve these 12 questions related to PXC! (you will find the answers at the end of the post.)
Workload
1. With Galera 3.x, support for MyISAM is experimental. When can
we expect to have full MyISAM support?
a. This will never happen as Galera is designed for transactional
storage engines.
b. This is planned for Galera 4.0.
2. Why aren’t all workloads a good fit for PXC?
a. Execution plans can change compared to a regular MySQL server,
so performance is sometimes not as good as with a regular MySQL
server.
b. Large …