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Measuring the potential overhead of PMM Client on MySQL workloads

Having good historial metrics monitoring in place is critical for properly operating, maintaining and troubleshooting database systems, and Percona Monitoring and Management is one of the options we recommend to our clients for this.

One common concern among potential users is how using this may impact their database’s performance. As I could not find any conclusive information about this, I set out to do some basic tests and this post shows my results.

To begin, let me describe my setup. I used the following Google Cloud instances:

  • One 4 vCPU instance for the MySQL server
  • One 2 vCPU instance for the sysbench client
  • One 1 vCPU instance for the PMM server

I used Percona Server 5.7 and PMM 1.5.3 installed via Docker. Slow query log was enabled with long_query_time set to 0 …

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More Write Set in MySQL: Group Replication Certification

This is the third post in the series on Write Set in MySQL.  In the first post, we explore how Write Set allows to get better parallel replication in MySQL 8.0.  In the second post, we saw how the MySQL 8.0 improvement is an extension of the work done in MySQL 5.7 to avoid replication delay/lag in Group Replication.  In this post, we will see how Write Set is used in Group Replication to detect

How to Install Snipe-IT Asset Management Software on Debian 9

Snipe-IT is a free and open source IT assets management web application that can be used for tracking licenses, accessories, consumables, and components. It is written in PHP language and uses MySQL to store its data. In this tutorial, we will learn how to install Snipe-IT on Debian 9 server.

Ten Tips on How to Achieve MySQL and MariaDB Security

Security of data is a top priority these days. Sometimes it’s enforced by external regulations like PCI-DSS or HIPAA, sometimes it’s because you care about your customers’ data and your reputation. There are numerous aspects of security that you need to keep in mind - network access, operating system security, grants, encryption and so on. In this blog post, we’ll give you 10 tips on what to look at when securing your MySQL or MariaDB setup.

1. Remove users without password

MySQL used to come with a set of pre-created users, some of which can connect to the database without a password or, even worse, anonymous users. This has changed in MySQL 5.7 which, by default, comes only with a root account that uses the password you choose at installation time. Still, there are MySQL installations which were upgraded from …

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Top 10 things to know about Alibaba Cloud RDS

Cloud-based Relational Database Services (RDS) offer businesses a variety of traditional Relational Database Management Systems (RDBMS) with several management and configuration options. In the Top 10 Things to Know about Amazon RDS blog, we covered Amazon RDS. In today’s article, we’ll be presenting Alibaba Cloud RDS. If you’ve been considering moving some or all of your database infrastructure to Alibaba Cloud RDS, or any Cloud RDS for that matter, there are many things to consider. Here are the top 10 things you need to know before taking the plunge.

About Alibaba Cloud RDS

Alibaba Cloud RDS, whose full name is Alibaba Cloud ApsaraDB for RDS, is an on-demand database service that handles some of the administrative tasks associated with managing a database, thus leaving you with more time to focus on your core business. …

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Possible ways to improve performance if you feel affected by Spectre and Meltdown

If you are concerned by performance degradation caused by Spectre and Meltdown patches it might be a good idea to do a few checks that will boost back your MySQL performance:

- Check if your instance’s CPU are running with full power:

cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

if the output is

powersave

You may benefit from setting CPU speed to performance mode

for i in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor ; do echo performance

Please refer to https://wiki.debian.org/HowTo/CpuFrequencyScaling and https://www.kernel.org/doc/Documentation/cpu-freq/governors.txt for more details.

- Check if your MySQL instances are configured properly. Buffer pool should …

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Why You Should Avoid Using “CREATE TABLE AS SELECT” Statement

In this blog post, I’ll provide an explanation why you should avoid using the CREATE TABLE AS SELECT statement.

The SQL statement “create table <table_name> as select …” is used to create a normal or temporary table and materialize the result of the select. Some applications use this construct to create a copy of the table. This is one statement that will do all the work, so you do not need to create a table structure or use another statement to copy the structure.

At the same time there are a number of problems with this statement:

  1. You don’t create indexes for the new table
  2. You are mixing transactional and non-transactional statements in one transaction. As with any DDL, it will commit current and unfinished transactions
  3. CREATE TABLE … SELECT …
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ProxySQL native HTTP server and metrics on a web UI

Introducing HTTP server in ProxySQL 1.4.4

ProxySQL exports a lot of metrics, all visible in the stats schema and queryable using any client that uses the MySQL protocol.
This allows to ingest metrics into external monitoring tools, like Percona PMM, grafana, Severalnines ClusterControl, graphite, datadog, and others already existing or being under development.

Although we believe these monitoring tools are the preferred and right way to monitor ProxySQL, we often faced the issue that ProxySQL isn’t monitored while still being evaluated. This makes very difficult the troubleshooting of performance and behavior in such scenarios. In fact, it is common that users report issues, but without metrics it is often very difficult to distinguish between a real performance bug, or a misconfiguration, or even issues completely unrelated to ProxySQL.
For this reason, ProxySQL version 1.4.4 introduces …

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MariaDB ColumnStore Distributed User Defined Aggregate Functions

MariaDB ColumnStore Distributed User Defined Aggregate Functions david.hall@mar… Wed, 01/10/2018 - 11:31

MariaDB ColumnStore 1.1 introduces the Distributed User Defined Aggregate Functions (UDAF) C++ API. MariaDB Server has supported UDAF (a C API) for a while, but now we have extended it to the ColumnStore Engine. This new feature allows anyone to create aggregate functions of arbitrary complexity for distributed execution in the ColumnStore Engine. These functions can also be used as Analytic (Window) functions just like any built in aggregate. You should have a working understanding of C++ to use this API.

The UDAF API supports an arbitrary number of parameters to be defined for your Aggregate function. Version 1.1 of ColumnStore supports one parameter and will be enhanced to support any number of parameters in the next version.

For …

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The Perfect Server CentOS 7.4 with Apache, Postfix, Dovecot, Pure-FTPD, BIND and ISPConfig 3.1

This tutorial shows how to install ISPConfig 3.1 on a CentOS 7.4 (64Bit) server. ISPConfig 3 is a web hosting control panel that allows you to configure the following services through a web browser: Apache web server, Postfix mail server, MySQL, BIND nameserver, PureFTPd, SpamAssassin, ClamAV, Mailman, and many more.

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