In this blog post, I will show you how to use Percona Monitoring and Management (PMM) to capture per-process metrics in five minutes or less.

While Percona Monitoring and Management (PMM) captures a lot of host metrics, it currently falls short providing per-process information, such as which particular process uses a lot of CPU resources, causes Disk IO or consumes a lot of memory.

In our database performance optimization and troubleshooting practice, this information has proven quite useful in many cases: batch jobs taking much more resources than developers would estimate and misconfigured Percona XtraBackup or Percona Toolkit are among the most common offenders.

Per-process metrics information can also be very helpful when troubleshooting database software memory leaks or memory fragmentation.

You …

MySQL, coupled with the InnoDB engine, provides full ACID compliance. With the addition of “eXtended Architecture” (XA) technology, they can all act in a distributed atomic environment.

In distributed systems, several different technologies, platforms and devices may need to act on separate sets of data atomically. These backend datasets can exist side by side in a datacenter, or across oceans. There can be multiple datasets where atomicity is a necessity. Foreign engines could completely control these datasets, with no concept of cross communication. The XA standard was specified by the Open Group to describe distributed transaction processing. This “eXtended Architecture” describes the relationship between a transaction manager and a transaction resource. You can find the specification HERE.

Transactions are:

• ATOMIC, committed as a …

Do you want to install MySQL 8.0 on Ubuntu 16.04 LTS? In this quick tutorial, I show you exactly how to do it in five minutes or less.

This tutorial assumes you don’t have MySQL or MariaDB installed. If you do, it’s necessary to uninstall them or follow a slightly more complicated upgrade process (not covered here).

Step 1: Install MySQL APT Repository

Ubuntu 16.04 LTS, also known as Xenial, comes with a choice of MySQL 5.7 and MariaDB 10.0.

If you want to use MySQL 8.0, you need to install the MySQL/Oracle Apt repository first:

wget https://dev.mysql.com/get/mysql-apt-config_0.8.10-1_all.deb
dpkg -i mysql-apt-config_0.8.10-1_all.deb

The MySQL APT repository installation package allows you to pick what MySQL version you want to install, as well as if you want access to Preview Versions. …

Yes, it does! In this blog post, I am going to share my recent experiences with ProxySQL and how important the database software version number can be.

Migration

I was working on a migration to Percona XtraDB Cluster (PXC) with ProxySQL, fortunately on a staging environment first so we could catch any issues (like this one).

We installed Percona XtraDB Cluster and ProxySQL on the staging environment and repointed the staging application to ProxySQL. At first, everything looked great. We were able to do some application tests and everything looked good. I advised the customer to do more testing to make sure everything works well. …

As part of my benchmarks of binary logs, I’ve decided to check how the recently released MySQL 8.0 performance is affected in similar scenarios, especially as binary logs are enabled by default. It is also interesting to check how MySQL 8.0 performs against the claimed performance improvements in redo logs subsystem.

I will use a similar setup as in my last blog with MySQL 8.0, using the utf8mb4 charset.

I have a few words about MySQL 8.0 tuning. Dimitri’s recommends in his blog posts using innodb_undo_log_truncate=off and …

I want to take a closer look at MySQL performance with binary logs enabled on different filesystems, especially as MySQL 8.0 comes with binary logs enabled by default.

As part of my benchmarks of the MyRocks storage engine, I’ve noticed an unusual variance in throughput for the InnoDB storage engine, even though we spent a lot of time making it as stable as possible in Percona Server for MySQL. In the end, the culprit was enabled binary logs. There is also always the question, “If there is a problem with EXT4, does XFS perform differently?” To answer that, I will repeat the same benchmark on the EXT4 and XFS filesystems.

You can find our previous experiments with binary logs here: …

Recently I worked on one customer issue that I would describe as “slave performance too slow”. During a quick analysis, I’ve found that the replication slave SQL thread cannot keep up while processing row-based events from the master’s binary log.

For example:

mysql> SHOW SLAVE STATUSG
*************************** 1. row ***************************
                          ...
              Master_Log_File: binlog.0000185
          Read_Master_Log_Pos: 86698585
                          ...
        Relay_Master_Log_File: binlog.0000185
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes
                          ...
          Exec_Master_Log_Pos: 380
              Relay_Log_Space: 85699128
                          ...
                  Master_UUID: …

In this blog post, I’m going to revisit the ProxySQL Query Rewrite feature. You may have seen me talking about possible use case scenarios in the past few conferences, but the reason I’m starting with this is that query rewriting was the original intention for building ProxySQL.

Why would you need to rewrite a query?

• You’ve identified a query that’s causing bottleneck or slowness
• A special operation requires query routing
• You cannot modify application code

So here we have a case of a bad query hitting the backend database. You as a DBA have identified the query as causing severe slowdown, which could lead to a site-wide outage. This query needs to be optimized, and you have asked the developer …

In this blog post, I’ll look at MyRocks performance through some benchmark testing.

As the MyRocks storage engine (based on the RocksDB key-value store http://rocksdb.org ) is now available as part of Percona Server for MySQL 5.7, I wanted to take a look at how it performs on a relatively high-end server and SSD storage. I wanted to check how it performs for different amounts of available memory for the given database size. This is similar to the benchmark I published a while ago for InnoDB (https://www.percona.com/blog/2010/04/08/fast-ssd-or-more-memory/).

In this case, I plan to use a sysbench-tpcc benchmark ( …

Percona Live 2018 is moving along, and the first person I got a chance to talk with is Michael Demmer, Senior Staff Engineer at Slack. His talk was on Migrating to Vitess at (Slack Scale).

MySQL is the backbone of Slack’s data storage infrastructure. It handles billions of queries per day across thousands of sharded database hosts. Slack is migrating this system to use Vitess’ flexible sharding and topology management instead of simple application-based shard routing and manual administration. This effort aims to provide an architecture that scales to meet the growing demands of our largest customers and features while under pressure to maintain a stable and performant service.

This talk presented the core motivations behind our decision, why Vitess won out as the best option, and how Slack laid the groundwork for the …