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Measuring Percona Server for MySQL On-Disk Decryption Overhead

Percona Server for MySQL 8.0 comes with enterprise grade total data encryption features. However, there is always the question of how much overhead – or performance penalty – comes with the data decryption. As we saw in my networking performance post, SSL under high concurrency might be problematic. Is this the case for data decryption?

To measure any overhead, I will start with a simplified read-only workload, where data gets decrypted during read IO.

During query execution, the data in memory is already decrypted so there is no additional processing time. The decryption happens only for blocks that require a read from storage.

For the benchmark I will use the following workload:

sysbench …
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Architecting reliable backup and recovery strategy


I have been managing multiple databases, mostly in Microsoft SQL Server and MySQL server, both on on-premise and cloud. We have faced a lot of challenging issues such as records deleted from a user table, backup file is corrupted, backup file is not compatible, backup files got deleted, backup storage is full and backup is running for long time, etc. When you are facing this issues for the first time, it is surprising to see new kind of issues every day and if you are not good in documentation, repetitive issues will keep occurring and we keep fixing rather than suctioning. If you are facing same challenges, then you need to focus on your backup and recovery strategy.


A well-designed backup and recovery strategy maximizes data availability and minimizes data loss without tolerating business requirement. In this post, we will discuss about the following topics:

  1. Recovery Time Objective (RTO)
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Impact of “tmpdir” change in MySQL replication

Recently we had encountered a strange issue with replication and temp directory(tmpdir) change while working for one major client.

All the servers under this were running with Percona flavor of MySQL versioned 5.6.38 hosted on a Debian 8(Jessie)

The MySQL architecture setup  is as follows one master with 5 direct slaves under it

Through this blog, we will take you through the issue we had faced and how we fixed ultimately.

Client Request:

There was a simple request from our client to add a column and index to a 16GB production table since the table had foreign keys, to avoid complications we decided to go with online DDL instead of pt-online-schema.

When we started to alter, it got failed due to insufficient space in “tmpdir”.MySQL by default would be using “/tmp” for temp table creating, sorting and other temp operation, Since we had only 5.7G left on the “/” …

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MariaDB MaxScale Masking Basics and Examples

I wanted to take a moment to write up a post on MariaDB MaxScale’s masking basics and include some real-world examples.

We have nice documentation on the subject, and Dipti wrote a nice blog post on it as well. I just wanted to provide my take on it, and hopefully build upon what is already there and offer some additional insights.

To provide a 50-foot overview, the masking filter makes it possible to obfuscate the returned value of a particular column.

3 quite common columns where this would be very beneficial: Social Security Number (“SSN”), Date of Birth (“DOB”), and Credit Card Number (“CCNUM”).

To use masking, it assumes you already have a MaxScale service up and running. For instance, the readwrite …

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MariaDB 10.3.13 and MariaDB Connector/C 3.0.9 now available

The MariaDB Foundation is pleased to announce the availability of MariaDB 10.3.13, the latest stable release in the MariaDB 10.3 series, as well as MariaDB Connector/C 3.0.9, the latest stable release in the MariaDB Connector/ODBC series. See the release notes and changelogs for details. Download MariaDB 10.3.13 Release Notes Changelog What is MariaDB 10.3? MariaDB […]

The post MariaDB 10.3.13 and MariaDB Connector/C 3.0.9 now available appeared first on MariaDB.org.

MySQL 8 is not always faster than MySQL 5.7

MySQL 8.0.15 performs worse in sysbench oltp_read_write than MySQL 5.7.25

Initially I was testing group replication performance and was puzzled why MySQL 8.0.15 performs consistently worse than MySQL 5.7.25.

It appears that a single server instance is affected by a performance degradation.

My testing setup

Hardware details:
Bare metal server provided by packet.net, instance size: c2.medium.x86
24 Physical Cores @ 2.2 GHz
(1 X AMD EPYC 7401P)
Memory: 64 GB of ECC RAM

Storage : INTEL® SSD DC S4500, 480GB

This is a server grade SATA SSD.

Benchmark

sysbench oltp_read_write --report-interval=1 --time=1800 --threads=24 --tables=10 --table-size=10000000 --mysql-user=root --mysql-socket=/tmp/mysql.sock run

In the following summary I used these combinations:

  • innodb_flush_log_at_trx_commit=0 or 1
  • Binlog: …
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JSON specific window functions in MySQL 8.0

In 8.0, we introduced window functions in the MySQL server. A detailed explanation of how window functions can be used and what is supported in 8.0 is explained here.

Now, let’s see what is new in window functions in the latest version 8.0.…

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MySQL 8.0 allows unprivileged user access to its data if table mysql.user does not exists

Yesterday my Percona colleague Ceri Williams found a nasty bug in MySQL 8.0. Its twin for Percona Server reported at PS-5431.

He was installing MySQL Server 8.0 having not supported option in his configuration file. Thus initialization failed, but, surprisingly, the subsequent restart was successful and he was able to create, modify and delete tables in his MySQL installation. In other words: he got full access to the database. But he did not create any user account yet!

This new instance of MySQL Server did not have privilege tables, particularly …

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How to Install MySQL on Ubuntu 18.04

In this tutorial, we will show you how to install and improve the security of MySQL on Ubuntu 18.04. MySQL ...

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The post How to Install MySQL on Ubuntu 18.04 appeared first on RoseHosting.

Percona Monitoring and Management (PMM) 1.17.1 Is Now Available

Percona Monitoring and Management (PMM) is a free and open-source platform for managing and monitoring MySQL®, MongoDB®, and PostgreSQL performance. You can run PMM in your own environment for maximum security and reliability. It provides thorough time-based analysis for MySQL®, MongoDB®, and PostgreSQL® servers to ensure that your data works as efficiently as possible.

In this release, we are introducing support for detection of our upcoming PMM 2.0 release in order to avoid potential version conflicts in the future, as PMM 1.x will not be compatible with PMM 2.x.

Another improvement in this release is we have updated the Tooltips for Dashboard MySQL Query Response Time by providing a description of what the graphs display, along with links to related documentation resources. An example of Tooltips in action:

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