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Displaying posts with tag: troubleshooting (reset)
Troubleshooting MySQL Performance Issues

Despite your very best efforts, as tables increase in size and more and more users come online, sluggish MySQL performance eventually rears its ugly head. When that happens, you may be tempted to shrug it off as part of doing business. Don’t. By understanding the mechanisms behind database slowdowns and by methodically attacking the problem, you can home in on the culprit(s) and remedy the issues in a timely manner, before your business suffers substantial losses as a result.

The purpose of this blog is to assist you in determining the cause(s) of MySQL database performance issues using a couple of built-in tools.

Why Database Performance Slows Down

It’s no secret that database performance tends to degrade over time. While it’s easy to point the finger at the number of concurrent users, table scans, and growing tables, the reality is more complex than that. The most common reason for slow database performance is …

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Stepicon 2017 and thoughts on MySQL MOOCs

I periodically do MySQL Troubleshooting tutorials. Every time I run them I have a dilemma on how to make tutorials more interactive. I tried:

  1. Just talk. But troubleshooting is about action, not about sitting and listening 
  2. Put tasks on my own website which required a lot of coding, not related to the talk and tasks themselves.
  3. Put tasks on VirtualBox image. Many attendees do not want to use flash drive or download big image from Internet.
  4. Put tasks into Amazon EC2 instance. This is practically good option, but expensive.
  5. Use machines, provided by tutorial organizers (conference or training center). This is, probably, the best option, but few do it.

I did not like any of these options as final solution. That's why for my last two tutorials I tried Stepik platform. This is how " …

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The story of MySQL Bug #86664

This is a story about why it's a good idea to test and verify the behavior of new software releases, even if the change log says that a particular bug was already fixed.
Background MySQL 5.6 and 5.7 both support the following CREATE USER syntax:

CREATE USER 'user'@'host'
  IDENTIFIED BY 'password';

This syntax create a user with the default authentication plugin (mysql_native_password unless configured otherwise) and the password provided. The IDENTIFIED BY syntax is also supported for GRANT command.
Both major versions also support the following syntax:

CREATE USER 'user'@'host'
  IDENTIFIED WITH mysql_native_password AS 'hash_string';

The password hash for "passw0rd" is "*74B1C21ACE0C2D6B0678A5E503D2A60E8F9651A3", you might then expect that the effects of the …

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Getting Started with MySQL Replication for High-Availability

Many organizations have MySQL or MariaDB databases at the core of their business—for processing and storing product sales, collecting information related to services offered, or just providing essential information to customers. As a result, keeping these databases running continuously can be critical for the success of an organization.

There are many components of a database system that a database administrator will need to consider for maintaining high availability. We considered server equipment (e.g., memory) in a previous introductory article. Now let’s look at using multiple servers for your MySQL and MariaDB databases—let’s look at replication.

Replication Overview

One common and effective way to structure a highly available database system is through some form of database replication. There are a few reasons …

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Getting Started with MySQL Replication for High-Availability

Many organizations have MySQL or MariaDB databases at the core of their business—for processing and storing product sales, collecting information related to services offered, or just providing essential information to customers. As a result, keeping these databases running continuously can be critical for the success of an organization.

There are many components of a database system that a database administrator will need to consider for maintaining high availability. We considered server equipment (e.g., memory) in a previous introductory article. Now let’s look at using multiple servers for your MySQL and MariaDB databases—let’s look at replication.

Replication Overview

One common and effective way to structure a highly available database system is through some form of database replication. There are a few …

[Read more]
Best practices for migrating databases to Amazon Aurora

If you like to read (a lot) and you're considering to migrate your database workloads to AWS, this might be something for you. Nearly 75 pages of ideas for planning, executing, and troubleshooting database migrations to Amazon Aurora.

I recently published an Aurora Migration Handbook in the form of an AWS Whitepaper. The document can be downloaded from here:

https://d0.awsstatic.com/whitepapers/Migration/amazon-aurora-migration-handbook.pdf

Happy reading!

TokuDB Troubleshooting: Q & A

In this blog, we will provide answers to the Q & A for the TokuDB Troubleshooting webinar.

First, we want to thank everybody for attending the March 22, 2017 webinar. The recording and slides for the webinar are available here. Below is the list of your questions that we were unable to answer during the webinar:

Q: Is it possible to load specific tables or data from the backup?

A: Do you mean the backup created by TokuBackup? No, this is not possible. You have to restore the full backup to a temporary instance, then perform a logical …

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Webinar Thursday 3/30: MyRocks Troubleshooting

Please join Percona’s Principal Technical Services Engineer Sveta Smirnova, and Senior Software Engineer George Lorch, MariaDB’s Query Optimizer Developer Sergei Petrunia and Facebook’s Database Engineer Yoshinori Matsunobu as they present MyRocks Troubleshooting on March 30, 2017 at 11:00 am PDT / 2:00 pm EDT (UTC-7).

Register Now

MyRocks is an alternative storage engine designed for flash storage. It provides great write workload performance and space efficiency. Like any other powerful engine, it has its own specific configuration scenarios that require special troubleshooting solutions.

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Troubleshooting Issues with MySQL Character Sets Q & A

In this blog, I will provide answers to the Q & A for the Troubleshooting Issues with MySQL Character Sets webinar.

First, I want to thank everybody for attending the March 9 MySQL character sets troubleshooting webinar. The recording and slides for the webinar are available here. Below is the list of your questions that I wasn’t able to answer during the webinar, with responses:

Q: We’ve had some issues converting tables from

utf8

  to

utf8mb4

. Our issue was that the collation we wanted to use –

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Troubleshooting MySQL access privileges issues: Q & A

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

First, I want to thank everybody for attending the February 23 webinar. The recording and slides for the webinar are available here. Below is the list of your questions that I wasn’t able to answer during the webinar, with responses:

Q: Should the root@localhost user be given ALL privileges or Super privileges? Does All include Super privileges also?

A: Yes, you should have a user with all privileges. Better if …

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