For what reason should I use a real multi-primary setup?

To be clear, not a multi-writer solution where any node can become the active writer in case of needs, as for Percona XtraDB Cluster (PXC) or Percona Server for MySQL using Group_replication. No, we are talking about a multi-primary setup where I can write at the same time on multiple nodes. I want to insist on this “why?”.

After having excluded the possible solutions mentioned above, both covering the famous 99.995% availability, which is 26.30 minutes of downtime in a year, what is left?

Disaster Recovery? Well, that is something I would love to have, but to be a real DR solution we need to put several kilometers (miles for imperial) in the middle.

And we know …

Maybe one of the more “obscure” operations when dealing with replica lag, or, in general, when one needs to control writes to the database, is the Rate limit. It’s also lately one of the most popular conversations around the community.

But what is it? In plain words: holding up queries for a while, giving air to the replicas to breath and catch up. Something similar to the Galera’s Flow Control mechanism, although flow control, when it kicks in, stops all the writes while the nodes catch up. With a throttle no write is stopped, just delayed.

There are several ways to do this. A popular tool is Freno but this is also something that can be achieved with ProxySQL. Let’s see how.

Delay

ProxySQL has a variable called …

A blog series about ProxySQL and Galera…

This post is the first of a series of blogposts on how to easily use ProxySQL to scale-out your application’s database workload on a Galera cluster. This series will explore the main concepts in configuring ProxySQL for Galera across three articles as follows:

– A first introductory post describing the minimal configuration needed for ProxySQL to monitor and manage a Galera Cluster.
– A second post describing how to setup a read/write split configuration for our Galera Cluster, using ProxySQL query rules.
– A third and final post with examples on specific cluster configuration options and more detailed explanations on why and how ProxySQL changes the nodes states based on configuration changes and monitored variables. Requirements

To illustrate how to configure ProxySQL for a Galera Cluster we will use a sample Galera Cluster …

ProxySQL participará en la próxima edición del evento open source “ESLIBRE”, que tendrá lugar los días 18th & 19th de Septiembre. La fecha coincidirá con el “Software Freedom Day”, día que celebra el Free Software en el mundo entero.

El desarrollador senior de ProxySQL, Javier Jaramago Fernández, expondrá “Introducción a ProxySQL”, haciendo hincapié en la importancia de limitar el downtime tanto como sea posible, además de, exponer que otras herramientas ofrece ProxySQL y cómo podemos hacer uso de ellas para mejorar nuestra infraestructura.

La charla se centrará en ProxySQL como proyecto, sus características, y la topología básica de su uso.
Se expondrán ejemplos en tiempo real de cómo usar estas características, como:

• Cambios de configuración con Zero-downtime – ProxySQL posee tres capas de …

ProxySQL will be taking part in the upcoming EsLibre, open source event on the 18th & 19th of September. The date also coincides with ‘Software Freedom Day’ which celebrates Free Software, all over the world.

ProxySQL’s Senior Developer, Javier Jaramango Fernandez, will be discussing ‘Introduction to ProxySQL’, focusing on the importance of limiting downtime as much as possible, as well as, the tools ProxySQL offers and how you can use them to improve your infrastructure.

The talk will focus on the introduction of ProxySQL as a project, its characteristics, and the basic topology for its use.
Real-time examples and how to use them will also be discussed, such as:

• Zero-downtime configuration changes – ProxySQL offers three configuration layers: memory, disk and runtime. Each of these layers can be configured dynamically, …

ProxySQL is proud to announce the release of the latest stable version of ProxySQL 2.0.14 on the 8th of September 2020

ProxySQL is a high performance, high availability, protocol aware proxy for MySQL, with a GPL license! It can be downloaded here or alternatively from the ProxySQL Repository, and freely usable and accessible according to the GNU GPL v3.0 license.

Release Overview Highlights

Before discussing the features and fixes in this release we’d like to mention that we are aware of the delays in new releases. Ideally we would like to release ProxySQL more rapidly however we have recently been focusing our development efforts on ProxySQL 2.1.

The next edition of ProxySQL brings improved performance as well as many new and exciting …

After spending four years working with ProxySQL in production, I’ve learned a few interesting lessons about interpreting and processing query rules. I hope to save you some time (and avoid wrong turns) with this summary of ProxySQL query rules.

ProxySQL query engine is very powerful and supports the building of complex rule sets. These can be used to route traffic to backend MySQL instances, rewrite queries, and for traffic mirroring, among other use cases.

When the rule set is short and simple, you can easily understand what the outcome for a certain query would be. However, for complex sets or combined scenarios, you need a deeper understanding of the engine logic.

Note 1: Rules are processed in rule_id order

It might seem like a trivial start, but during testing or implementation, …

We sometimes receive challenging requests… this is a story about one of those times.

The customer has implemented a sharding solution and would like us to review alternatives or improvements. We analyzed the possibility of using ProxySQL as it looked to be a simple implementation. However, as we had 200 shards we had to implement 200 rules — the first shard didn’t have much overload, but the latest one had to go through 200 rules and took longer.

My first idea was to use FLAGIN and FLAGOUT creating a B-Tree, but the performance was the same. Reviewing the code, I realized that the rules were implemented as a list, which means that, in the end, all the rules were going to be processed until hit with the right one and FLAGIN is used just to filter out.

At that point, I asked, what could I do? Is it possible to implement it differently? What is the performance impact?

One Problem, Two Solutions

I …

ProxySQL brings a lot of value to your MySQL infrastructures such as Caching or Connection Multiplexing but it does not come free — your database needs to go through additional processing traffic which adds some overhead. In this blog post, we’re going to discuss where this overhead comes from and measure such overhead. 

Types of Overhead and Where it Comes From 

There are two main types of overhead to consider when it comes to ProxySQL — Network Overhead and Processing Overhead. 

Network Overhead largely depends on where you locate ProxySQL. For example, in case you deploy ProxySQL on the separate host (or hosts) as in this diagram: 

The application will have added network latency for all requests, compared to …

Owing to the success and feedback we received from our last training course, we will be running another 2 sessions, both for European, as we well as Pacific Time zones

Delivered by our Professional ProxySQL Trainers who have built and actively maintain ProxySQL.

ProxySQL was built in order to help build, support and improve MySQL infrastructure.

Our public 2x Day Training course will help you learn about how to use ProxySQL’s features effectively and to efficiently deal with real life events and emergency situations in your infrastructure.

The rich course content provides insights to help you build a strong understanding of the tool’s design goals, and most importantly… how to properly implement ProxySQL in order to maximize the resource utilization of your database cluster while avoiding common pitfalls and anti-patterns!

Immerse yourself in the world of ProxySQL with our two-day …