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Displaying posts with tag: MySQL (reset)
Lightning talks at Percona Live Data Performance Conference

The main schedule for the Percona Live Data Performance Conference is available. Almost everything has been defined. There are tutorials and plenty of sessions waiting for conference attendees.

One thing that is still undefined is the session of lightning talks. The …

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How To Speed Up MySQL Restart (hint: just like before, but this time for real)

Restating MySQL can be really annoying. You just want to disable the goddamn query cache and it takes forever (read 5-10 minutes) to shutdown, not to mention the warm-up time. Yes, with MySQL 5.7 you can do many changes online, so you won’t necessarily be restarting that often, but you still need to do upgrades, occasionally increase redo log size and, admit it, enable skip-grant-tables. Here’s how you can make this process way less painful.

Why is MySQL so slow to restart?

Before we go any further, let me tell you right away that when I’m speaking about MySQL here, I’m actually speaking about InnoDB, or rather, a MySQL server that’s running InnoDB as the main storage engine. And if that’s not your case, do not read any further. You’ve been warned!

Now.. ah yes. Restart. So, restarting MySQL involves two slow stages. I have already mentioned them, but repetition is the mother of skill, so let me say …

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OmniSQL – Massively Parallel Query Execution

A few years ago, I wrote the original OmniSQL as a Perl script to automate the execution of queries across many MySQL servers and, in some cases, provide basic aggregation functionality. Shortly after that time, Justin Swanhart released Shard-Query and Domas Mituzas released pmysql, so OmniSQL was retired.

I’m a daily user of pmysql; indeed, we run a heavily patched version. Lately, I find myself needing to extend the functionality even more than we’ve already done. After a bit of evaluation, I decided that C wasn’t the best language to move forward with the new features. Thus, OmniSQL is reborn in Go. While initial testing indicates that it is an order of magnitude slower than pmysql running against 1,000+ instances of MySQL, it’s still well within my tolerance (and there are many areas of …

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Experimental Percona Docker images for Percona Server

Docker is incredibly popular tool for deploying software, so we decided to provide a Percona Docker image for both Percona Server MySQL and Percona Server for MongoDB.

We want to create an easy way to try our products.

There are actually some images available from https://hub.docker.com/_/percona/, but these images are provided by Docker itself, not from Percona.

In our images, we provide all the varieties of storage engines available in Percona Server (MySQL/MongoDB).

Our images are available from https://hub.docker.com/r/percona/.

The simplest way to get going is to run the following:

docker run --name ps -e MYSQL_ROOT_PASSWORD=secret -d …
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New and old ways to emulate CHECK constraints, DOMAIN

Correctness of data comes in different forms. One is referential integrity, also known as foreign keys. Another is CHECK constraints. While MySQL supports foreign keys, it doesn’t support CHECK constraints. Today we will look at three ways to emulate them:

  • triggers
  • views
  • generated columns (new in MySQL 5.7)

This is also relevant to another SQL feature: DOMAIN, which, in short, is a user-defined type composed of a base type (INT, CHAR, …), a default value, and a constraint on acceptable values – the latter being some simple sort of CHECK constraint.…

MySQL Enterprise Backup (MEB) and Oracle Storage Cloud

MEB 3.12.0 and above support cloud backup and restore using OpenStack-compatible object stores ("Swift"). This allows MySQL database users with Oracle Storage Cloud account to take backups and store them directly in the cloud and restore them from there.

The following steps illustrate how to set up and use MEB with Oracle Storage Cloud :

1) Create Oracle Storage Cloud account at https://cloud.oracle.com/storage . Once service gets activated, make a note of the following credentials that will be required in further steps :

  • Username

  • Password

  • Identity domain name

  • Service Instance Name : Customer-specified name of the service instance

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Extend MySQL Master HA (MHA) capabilities with MHA Helper

I have used many tools starting with MMM to be able to manage MySQL replication clusters. Some of the tools need more tools and complex HA solutions such as Pacemaker and Corosync, or Zookeeper. While other tools do not do the failover well which leaves the slaves in an inconsistent state, MMM would be an example. And I must say that of all the tools I love MySQL Master HA (MHA) the most. MHA is a great tool to manage MySQL replication clusters for the purpose of HA. The most important thing about MHA is that it tries to take all the necessary steps to do a MySQL master failover in a way that provides as much data consistency as possible. The slave promotion also tends to be very quick, on average I have seen it take 10 to 15 seconds. It is also very easy to deploy unlike some of the other complex HA solutions. I would highly recommend reading about the architecture of MHA on its wiki: https://code.google.com/p/mysql-master-ha/wiki/Architecture Why …

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Log Buffer #458: A Carnival of the Vanities for DBAs

This Log Buffer Edition covers various useful tips and tricks from blogs for Oracle, SQL Server and MySQL.

Oracle:

  • pstack(or thread stack) for Windows to diagnose Firefox high CPU usage
  • With the ever-changing browser landscape, we needed to make some tough decisions as to which browsers and versions are going to be deemed “supported” for Oracle Application Express.  There isn’t enough time and money to support all browsers and all versions, each with different bugs and varying levels of support of standards.
  • Are you effectively using Java SE 8 streams …
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A safer MySQL box in Docker

The MySQL team has been maintaining a MySQL image on Docker. They have been listening to requests from the community and reacting quickly. So far, they have fixed two bugs that I reported and introduced a feature request that I suggested to make the server more secure.

Thanks, folks!

My latest request was about password management in a MySQL container. I have mentioned in previous posts the compatibility problems introduced by MySQL 5.7 security enhancements. Let me recap the main issues here:

MySQL is secure by default.

The recommended method to install MySQL is mysqld --initialize, which will generate a random password that the DBA will then use to access the …

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Extend MySQL Master HA (MHA) capabilities with MHA Helper

I have used many tools starting with MMM to be able to manage MySQL replication clusters. Some of the tools need more tools and complex HA solutions such as Pacemaker and Corosync, or Zookeeper. While other tools do not do the failover well which leaves the slaves in an inconsistent state, MMM would be an example.
And I must say that of all the tools I love MySQL Master HA (MHA) the most. MHA is a great tool to manage MySQL replication clusters for the purpose of HA. The most important thing about MHA is that it tries to take all the necessary steps to do a MySQL master failover in a way that provides as much data consistency as possible. The slave promotion also tends to be very quick, on average I have seen it take 10 to 15 seconds. It is also very easy to deploy unlike some of the other complex HA solutions.

I would highly recommend reading about the architecture of MHA on its wiki: …

[Read more]
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