In this post, we’ll look at the MySQL 8.0 innodb_dedicated_server variable.

MySQL 8.0 introduces a new variable called innodb_dedicated_server. When enabled, it auto tunes innodb_buffer_pool_size, innodb_log_file_size and innodb_flush_method at startup (if these variables are not explicitly defined in my.cnf).

The new MySQL 8.0 variable automatically sizes the following variables based on the RAM size of the system:

innodb_buffer_pool_size:

• • <1G: 128M(default value if innodb_dedicated_server is OFF)
  • <=4G: Detected Physical RAM * 0.5
  • >4G: Detected Physical RAM * 0.75

innodb_log_file_size: …

Introduction

In my travels to visit many customers over the last few years, I often see my customers creating many or all of their MySQL InnoDB tables using auto-increment primary keys. Many Object Relational Mappers do this by default on behalf of the user. Once the tables are all created with auto increment primary keys, then the database designer/developer goes about assigning alternate keys that they will actually use to access the data. Most of the time the auto-increment key is simply there to ensure that there is a unique key on the table and it’s often not used as an access path. This is a common design pattern, but is it the best way to create tables using MySQL? I am witting this blog to present the case that it’s a pretty bad idea most of the time.

Why it’s a bad Idea

There are four reasons why, which I will explain in some depth later in the post but for now, they are:

• Auto increment keys …

In this blog post, We will be explaining about the timeouts in SST on systemd implementation which we faced recently in Percona XtraDB Cluster  during our Consulting with a client. State Snapshot Transfers (SST) refers to complete data sync from one of the nodes from the cluster to the joining node.

SST will happen for one or more reasons listed below.

1. Initial sync to join a node to cluster.
2. Node is out of cluster and lost its ability to join back due to data corruption or inconsistencies and also when the node went far behind the node, …

This is our second blog in the ProxySQL Series ( Blog I MySQL Replication Read-write Split up ). Will cover how to integrate ProxySQL with MHA to handle failover of Database servers.

We already have Master – Slave replication setup behind ProxySQL from previous blog [ProxySQL On MySQL Replication]

For this setup we have added one more node for MHA Manager , Which will keep eye on Master and Slave status.

• node5 (172.17.0.5) , MHA Manager

ProxySQL can be greatly configured with MHA for …

In this post, We will learn how to handle online schema change if the table has triggers.

In PXC, an alter can be made directly ( TOI ) on tables with less than a 1G ( by default) , but on a 20GB or 200GB table we need some downtime to do ( RSU ).

Pt-osc is a good choice for Percona Cluster/Galera. By default percona toolkit’s pt-online-schema-change will create After “insert / update / delete” triggers for maintaining the sync between the shadow and the original table.

pt-online-schema-change process flow:

Check out the complete slides for effective MySQL administration here

If the tables has triggers already then pt-osc wont work well in …

Security is one of the hottest topics lately, and in this blog post, I will walk you through what needs to be configured to have a working three-node Percona XtraDB Cluster running with InnoDB Tablespace Encryption enabled.

This article will not cover the basics of setting up a cluster nor will it cover how to create SSL certs and keys since both of these topics have been well explained here and here.

Just to give you a brief history, InnoDB tablespace encryption was introduced in MySQL 5.7.11, and starting from …

The ability to restore MySQL logical backups is a significant part of disaster recovery procedures. It’s a last line of defense.

Even if you lost all data from a production server, physical backups (data files snapshot created with an offline copy or with Percona XtraBackup) could show the same internal database structure corruption as in production data. Backups in a simple plain text format allow you to avoid such corruptions and migrate between database formats (e.g., during a software upgrade and downgrade), or even help with migration from completely different database solution.

Unfortunately, the restore speed for logical backups is usually bad, and for a big database it could require days …

Percona announces the GA release of Percona Server for MySQL 5.7.21-20 on February 19, 2018. Download the latest version from the Percona web site or the Percona Software Repositories. You can also run Docker containers from the images in the Docker Hub repository.

Based on MySQL 5.7.21, including all the bug fixes in it, Percona Server for MySQL 5.7.21-20 is the current GA release in the Percona Server for MySQL 5.7 series. Percona …

In this blog, I will provide answers to the Q & A for the Troubleshooting MySQL Crashes webinar.

First, I want to thank everybody for attending our January 25, 2018, webinar. The recording and slides for the webinar are available here. Below is the list of your questions that I was unable to answer fully during the webinar.

Q: I have the 600 seconds “Long semaphore wait” assertion failure / crashing issue following DDL queries, sometimes on the master, sometimes just the slaves. Any hints for troubleshooting these? How can I understand what semaphore holding …

I was involved in one of the development support for MySQL. Here is an interesting case

The application needs a Sequence generator as it was not present inbuilt with MySQL ( MariaDB will have it in 10.3 ) they have made sequence generator function with ‘select for update‘ statement. But it tends to cause more locking at high concurrency with their XtraDB Cluster deployment.

To get rid of this , the sequence generation were made as direct Update queries and sequence is fetched using Select @next.

UPDATE EO_PK_TABLE SET PK = (@next := PK …