Ideas, releases, practical guides, and perspectives from the people building with MySQL.
We’ve released Percona Toolkit 2.0.3, with a couple of major improvements and many minor ones. You can download it, read the documentation, and get support for it.
What’s new? You can read the changelog for the details, but here are the highlights:
Brand new pt-diskstats, thanks to Brian Fraser. This tool is completely rewritten, and it’s finally the iostat replacement I always wanted. Not only does it have the functionality I want (interactive, slice and dice, smart …
[Read more]Sometimes we need to restore only some tables from a full backup maybe because your data loss affect a small number of your tables. In this particular scenario is faster to recover single tables than a full backup. This is easy with MyISAM but if your tables are InnoDB the process is a little bit different story.
With Oracle’s stock MySQL you cannot move your ibd files freely from one server to another or from one database to another. The reason is that the table definition is stored in the InnoDB shared tablespace (ibdata) and the transaction IDs and log sequence numbers that are stored in the tablespace files also differ between servers. Therefore our example will be very straightforward: we’ll delete some rows from a table in order to recover the table later.
Most of these limitations are solved on Percona Server . More info about this in the conclusion section of this post. This post will …
[Read more]This is about the second great feature – Multi-Master replication, what you get with Percona XtraDB Cluster.
It is recommended you get familiar with general architecture of the cluster, described on the previous post.
By Multi-Master I mean the ability to write to any node in your cluster and do not worry that eventually you get out-of-sync situation, as it regularly happens with regular MySQL replication if you imprudently write to the wrong server.
This is long-waited feature, I’ve seen growing demand for it for
last two years or even more.
Percona XtraDB Cluster provides it, and let’s see how it
works.
With our Cluster you can write to any node, and the Cluster …
[Read more]There and in coming posts I am going to cover main features of Percona XtraDB Cluster. The first feature is High Availability.
But before jumping to HA, let’s review general architecture of
the Percona XtraDB Cluster.
1. The Cluster consists of Nodes. Recommended configuration is to
have at least 3 nodes, but you can make it running with 2 nodes
too.
2. Each Node is regular MySQL / Percona Server
setup. The point is that you can convert your existing MySQL /
Percona Server into Node and roll Cluster using it as base. Or
otherwise – you can detach Node from Cluster and use it as just a
regular server.
3. Each Node contains the full copy of data.
That defines XtraDB Cluster behavior in many ways. And obviously
there are benefits and drawbacks.
Benefits of such approach:
I understand that the new technology can be scaring and this
makes entry barriers to try and get familiar with it.
That’s why I created simple set of scripts which setup N nodes
cluster on running EC2 instances.
The script assumes that you have running N EC2 instances (in the
same availability zone) running RedHat Enterprise Linux 6.2 64bit
(I use m1.xlarge size).
You put hostnames of the instances into ec2hosts.txt
file and run install.nodes.sh script.
You also should have your private key to access to your instances
(test-cluster.pem in my case).
For my box installing and starting 3 nodes took exactly
time install.nodes.sh ... real 2m51.257s
In fact you can deploy as many nodes as you want, I made also running 20 nodes cluster.
After that you have the cluster deployed and ready to accept queries!
The scripts are …
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In this post I want to show new possibilities which open with
Percona XtraDB Cluster.
We will create 3 nodes Cluster with nodes on different continents
(Europe, USA, Japan) and each node will accept write
queries.
Well, you theoretically could create 3 node traditional MySQL
ring replication, but this is not what you want to use
day-to-day.
To show how it works I will use Amazon m1.xlarge instances, by
one in Tokyo, Ireland and North California, running RedHat
Entreprise 6.2 64bit.
In fact to create instances is most time consuming task. After that using my script you will have cluster running in 5 min or less.
There however some precautions needed if you run Amazon
instances.
First, you need to open ports in the firewall. For the
communication the nodes need, …
You probably saw that Vadim blogged about the first alpha release of Percona XtraDB Cluster. Just in time: now I can talk about it at my High Availability talk in Percona Live DC! If you’re coming, be sure to catch us in the hallway and ask those specific questions that won’t be addressed in a general survey talk on HA solutions.
I am happy to announce the availability of alpha release of our new product Percona XtraDB Cluster.
Percona XtraDB Cluster is High Availability and Scalability solution for MySQL Users and based on Percona Server 5.5.17
Percona XtraDB Cluster provides:
Percona XtraDB Cluster is fully compatible with MySQL or Percona Server in the following meaning:
I got a question a while ago about how Percona Server handles corrupted data more gracefully than the standard MySQL server from Oracle. The short version is that it won’t crash the whole server.
With standard MySQL from Oracle, if any page of data in InnoDB is found to be corrupt, the entire instance will crash forcefully. This is a good policy if you want to treat your entire data set as a single unit, which is either usable or not. However, this does not reflect reality for many users, who have a lot of data collocated in a single instance. In such cases, it is desirable for the server to continue running, so the corruption in one database does not affect the others.
Percona Server handles corruption more gracefully, if you enable it, by simply marking the single table as corrupt, and not crashing the entire server.
The relevant documentation is …
[Read more]I’m happy to announce that we’ve released Percona Toolkit 2.0.1, a major new version of our essential DBA toolkit, as well as a minor bugfix update to the old 1.0.x series. You can download it from the project homepage, or install it through our RPM and DEB repositories.
Documentation is online (and the 1.0 docs are here), and you can come learn more in-person at the Washington DC Percona Live event next week. …
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