From MySQL 5.7, we had a Multi-threaded Slave (MTS) Applier mechanism called LOGICAL_CLOCK to overcome the problems of parallel replication within a database.

To further improve the parallelisation mechanism, from MySQL 8 (5.7.22) we have write-set replication, so before going further , lets look at the difference between Logical clock (LC) and Writeset.

LOGICAL_CLOCK

Transactions that are part of the same binary log group commit on a master are applied in parallel on a slave. The dependencies between transactions are tracked based on their timestamps to provide additional parallelisation where possible.

WRITESET

Write-set is a mechanism to track independent transactions that can be executed in parallel in the slave. Parallelising on write sets has potentially much more parallelism than logical_clock ,since it does not depend …

This post was written by:

Nicolas De Rico: Oracle Cloud Solutions Engineer - MySQL

Sergio J Castro: Oracle Cloud Solutions Engineer - Networking

From RDS to MDS

When an application reaches the maximum capabilities offered by Amazon Web Services (AWS) RDS, it is often recommended to migrate to the AWS Aurora service.   However, Aurora is based on an older version of MySQL.  Aurora still does not support MySQL 8.0, which was released in April 2018.  Therefore, it may be difficult to port applications to Aurora, and later, out of Aurora because of its proprietary aspects.

Defy conventional wisdom by upgrading from RDS to MDS and access many benefits

Instead of …

Upgrade from AWS RDS to the OCI MySQL Database Service (MDS) for complete MySQL support and functionality, and improved performance and security.

The goal of this blog post is to explain the various types of transaction isolation levels available in MySQL. After reading the blog, you will be able to explain dirty reads, non-repeatable reads, and the concept of phantom rows as well.

What is the Isolation Level in MySQL?

Isolation (I) is one of the properties from ACID. It defines how each transaction is isolated from other transactions and is a critical component of application design. As per the SQL:1992 standard, InnoDB has four types of Isolation levels. Below, I have listed the types in order, and each transaction isolation level provides better consistency compared to the previous one.

• READ-UNCOMMITTED
• READ-COMMITTED
• REPEATABLE-READ – ( MySQL’s DEFAULT )
• SERIALIZABLE

You can change the isolation level using the variable “transaction_isolation” at runtime. As transaction isolation changes can …

In this  blog series, I’m describing how InnoDB locks data (tables and rows) in order to provide illusion to clients that their queries are executed one after another, and how this was improved in recent releases.
In InnoDB Data Locking – Part 1 “Introduction” I’ve introduced basic concepts required to understand current post:

• databases, tables, rows (like files on a shared drive, spreadsheets inside a file, and rows inside a spreadsheet)
• serializability of transactions (ability to explain states observed over time with a convincing story about relative order of parallel operations)
• timeouts (for misbehaving lock owners, and to resolve deadlocks)
• reader-writer lock …

While it's easier to measure the impact of Dynimize if you are running a MySQL benchmark with clear metrics, it can sometimes be a challenge on a production workload where you don't have precise performance analytics or metrics available. There are many great MySQL performance analysis tools out there, however they can often take time and effort to setup.

The simple measureDyniMysql script was created for this exact reason, and does not incur any MySQL downtime. You can find it at /opt/dynimize/measureDyniMysql after installing Dynimize. It will report the change in MySQL queries per second and mysqld CPU usage after applying Dynimize. Here is how to use it.

1. Install and start dynimize, and get your mysqld process into the dynimized state. For example, the …

MySQL is the number one open source relational database management system in the world, and is used by millions of developers across all application types. DigitalOcean, a fast-growing cloud provider that’s increasing in popularity amongst the developer community, is a great host to consider for your MySQL deployments. In this article, we’re going to show […]

 FOSDEM has become one of the biggest shows on the calendar of the MySQL Community Team.  FOSDEM itself, until this year, is barely contained chaos at a university in Brussels with no pre-enrollment for any of the dozens of themed rooms and no head count.  This year the event is virtual so you do not have to get to Belgium.

The MySQL and Friends Developer Room is Sunday and starts at 10:00am  Belgium time with a retrospective of the first twenty five years of MySQL. This is followed 15 other talks of about 25 minutes on everything from ARM to user management. 

Join Brian Walters and Brandon Fleisher for an interactive discussion around new service and software offerings coming from Percona.

Oracle has decided that MySQL 5.6 will reach its end of life in February 2021. This means there will be no more updates and, more importantly, no more security fixes for discovered vulnerabilities. Yikes! Did you know you have options? Did you know Percona can solve this problem? Tune in to find out how.

Choosing a database-as-a-service (DBaaS) provider can be a daunting challenge. Not ready to move to DBaaS in the public cloud? Or, are you constrained to on-prem deployment due to regulations or other market conditions? Tune-in to learn how Percona is bringing the benefits of simplified DBaaS deployment to the on-prem, private cloud, and hybrid datacenter.

This interactive webinar will be conducted in a roundtable forum style. Bring your interests, bring …

We are happy to announce another MySQL Webinar on the topic of "", see details below:

• Date: Feb 16, 2021
• Time: 2:00 pm Dubai time (GMT+4)
• Topic: Best practices for MySQL Performance
• Description: Of all the features that are available in MySQL, we will still need to optimize and fine tune our environment to our specific needs and the immediate or not-too-distant future growth. In this session we will have a look into ways to analyze the instances' performance and take into consideration some suggestions and best practices.
• Speaker: Carsten Thalheimer, the MySQL Master Principal Sales Consultant
• Registration …