Showing entries 1 to 10 of 25
10 Older Entries »
Displaying posts with tag: Mastering Tungsten Clustering (reset)
Make It Faster: Improving MySQL Write Performance for Tungsten Cluster Slaves

Overview The Skinny

In this blog post we explore various options for performance tuning MySQL server for better slave replication performance.

A Tungsten Cluster relies upon the Tungsten Replicator to move events from the master node to the slaves. Once the event has been transferred to the slave as THL on disk, the slave applier will then attempt to write it to the database. The Replicator can only apply events as fast as MySQL allows. If the MySQL server is somehow slow or blocking, then the Replicator will be as well.

A properly-tuned database server in addition to infrastructure and SysAdmin best practices will go quite a long way towards high-performance slave apply.

The Question Recently, a customer asked us:

During one of our load tests, we had a peak of 60k writes/min, averaging …

[Read more]
Read the White Paper: Tungsten Clustering for MySQL, MariaDB & Percona Server Databases

We’re happy to announce that our white paper ‘Tungsten Clustering – Benefits & Configurations’ for MySQL, MariaDB and Percona Server is available to read on our website.

Tungsten Clustering is a one-of-a-kind software solution that provides clustering, disaster recovery and high availability for MySQL, MariaDB & Percona Server databases.

It allows enterprises running business-critical database applications to cost-effectively achieve continuous operations on a global scale with:

  • Commercial-grade high availability (HA)
  • Geographically redundant disaster recovery (DR)
  • Global operations with geographically distributed multi-master

[Read more]
Handling Bi-Directional Replication between Tungsten Clusters and AWS Aurora

Overview The Skinny

In this blog post, we explore the correct way to implement bi-directional Tungsten Replication between AWS Aurora and Tungsten Clustering for MySQL databases.

Background The Story

When we are approached by a prospect interested in using our solutions, we are proud of our pre-sales process by which that we engage at a very deep technical level to ensure the we provide the best possible solution to meet with the prospect’s requirements. This involves an in-depth hands-on POC, in addition to the significant time and effort we spend building and testing the solution architectures in our lab environment as part of the proposal process.

From time to time, we are presented with requirements that are not always quite so straight forward. Just recently we faced such a situation. A …

[Read more]
Zero-Downtime Cluster Maintenance: Comparing the Procedures for Upgrades versus DB/OS Maintenance

Overview The Skinny

Part of the power of Tungsten Clustering for MySQL / MariaDB is the ability to perform true zero-downtime maintenance, allowing client applications full access to the database layer, while taking out individual nodes for maintenance and upgrades. In this blog post we cover various types of maintenance scenarios, the best practices associated with each type of action, and the key steps to ensure the highest availability.

Important Questions Understand the Environment as a Whole First

There are a number of questions to ask when planning cluster maintenance that are critical to understand before starting.

For example:

  1. What is the cluster topology?
    • Standalone (connectors write to single cluster master)
      Single cluster: …
[Read more]
How to use Round-Robin Load Balancing with the Tungsten Connector

Overview The Skinny

Part of the power of Tungsten Clustering for MySQL / MariaDB is its intelligent MySQL Proxy, known as the Tungsten Connector. The Tungsten Connector has built-in read-write splitting capabilities, and it is also possible to configure different algorithms which select the appropriate slave (i.e. Round-Robin or Lowest-Latency).

The Question Recently, a customer asked us:

How do we best share the load between read-only slaves? Currently, there appears to be an imbalance, with most of the read-only queries reaching just one slave. What may we do to improve this situation?

This customer noticed that a couple of long …

[Read more]
Enabling Autorecovery for the Tungsten Replicator

The Replicator is a critical piece of the Tungsten Clustering solution for MySQL / MariaDB, as well as its own stand-alone data replication product. Automatic recovery is a feature that enables the Replicator to go back online in the event of a transient failure. In this blog we discuss how to enable Automatic Recovery. For more information about Auto-Recovery, please click here to visit the online documentation page.

The Question Recently, a customer asked us:

We see that the replicators receive a transaction which has a deadlock error in it:

pendingError : Event application failed: seqno=82880882 fragno=0 message=java.sql.SQLTransactionRollbackException: Deadlock found when trying to get lock; try restarting transaction

If one performs a service online, it comes back online without issue and continues …

[Read more]
In a proxy-ed world, where do connections come from?

Overview The Skinny

Database Proxies provide a single entry point into MySQL for the calling client applications.

Proxies are wonderful tools to handle various situations like a master role switch to another node for maintenance, or for transparency with read and write connections.

However, when the time comes to perform the switch action, all of the calling clients have been funneled through the proxy, so identification of the calling host from the database itself becomes difficult.

The Problem What is going on?

Let’s illustrate how not knowing the source of a client connection can be an issue for the database administrator…

In the following diagram, three client applications connect to a Tungsten Cluster via the Connector proxy:

[Read more]
How to move the Relay role to another node in a Composite Tungsten Cluster

The Question Recently, a customer asked us:

How would we manually move the relay role from a failing node to a slave in a Composite Tungsten Cluster passive site?

The Answer The Long and the Short of It

There are two ways to handle this procedure manually when the usual switch command fails to work as expected. One is short and reasonably automated, and the other is much more detailed and manual.

Of course, the usual procedure is to just issue the switch command in the passive cluster:

use west
set policy maintenance
switch
set policy automatic

The below article describes what to do when the switch command does not move the relay role to another node.

SHORT

Below is the list of cctrl commands that would be run for the basic, short version, which (aside from handling policy changes) is really only …

[Read more]
How can I tell which Tungsten Connector mode I am using: Bridge, Proxy/Direct or Proxy/SmartScale?

Overview The Skinny

Part of the power of Tungsten Clustering for MySQL / MariaDB is its intelligent MySQL Proxy, known as the Tungsten Connector. Tungsten Connector has three main modes, and depending on the type of operations you are performing (such as if you need read-write splitting), we help you choose which mode is best.

The Question Recently, a customer asked us:

How can I tell which Tungsten Connector mode I am using: Bridge, Proxy/Direct or Proxy/SmartScale?

The Answer Connect and Observe

You may login through the Connector to tell the difference between Bridge mode and Proxy mode (either Direct or SmartScale):

In Proxy mode, you will see the -tungsten tag appended to the Server version string:

[Read more]
Slick Command-Line Tricks for a Tungsten MySQL / MariaDB Database Cluster

Overview The Skinny

Tungsten Clustering provides high availability, disaster recovery, and a host of other benefits for MySQL / MariaDB / Percona Server databases. In this blog post we will explore some of the shell aliases I use every day to administer various Tungsten Clusters.

Shell Aliases: A Quick Review Quick and Easy

A shell alias is simply a way to create a shortcut for frequently-used command sequences.

For example, I like to shorten the command clear to cls, i.e.

shell> alias cls=clear
shell> cls

If you create an alias on the fly it will be lost when the shell exits.

To save aliases so they are available to all shell sessions, update your shell’s profile or rc script.

For example, add the below line to the bottom of …

[Read more]
Showing entries 1 to 10 of 25
10 Older Entries »