Monthly Archives - February 2016

EXPLAIN FORMAT=JSON: nested_loop makes JOIN hierarchy transparent


Once again it’s time for another EXPLAIN FORMAT=JSON is cool! post. This post will discuss how EXPLAIN FORMAT=JSON allows the nested_loop command to make the JOIN operation hierarchy transparent.
The regular
EXPLAIN  command lists each table that participates in a 
JOIN  operation on a single row. This works perfectly for simple queries:


mysql> explain select * from […]

Read more

Graphing MySQL performance with Prometheus and Grafana

Graphing MySQL performance

This post explains how you can quickly start using such trending tools as Prometheus and Grafana for monitoring and graphing of MySQL and system performance.
Update, February 20, 2017: Since this blog post was published, we have released Percona Monitoring and Management (PMM), which is the easiest way to monitor MySQL and MongoDB using Grafana and […]

Read more

Monitoring MongoDB Response Time

In this blog post, we’ll discuss how using Prometheus can help with monitoring MongoDB response time. I am currently comparing the performance of different storage engines on Percona Server for MongoDB, using a slightly customized version of Tim Callaghan’s sysbench-mongodb. Since I’m interested in measuring response time for database operations, I created a very simple exporter of response […]

Read more

Percona Back to Basics: MongoDB updates

Welcome to the first in a new series of MongoDB blogs. These blogs will cover a selection of topics, including:

New release and new features
Getting back to the basics
Solutions from the field

In this first blog, we’ll discuss MongoDB updates. You can use the update method to update documents in a collection. MongoDB updates are well-covered […]

Read more

High availability with asynchronous replication… and transparent R/W split

High availability with asynchronous replication

In this post, the first one of a Maxscale series, I describe how to use MariaDB’s MaxScale and MySQL-utilities with MySQL Asynchronous replication.
When we talk about high availability with asynchronous replication, we always think about MHA or PRM. But if we want to transparently use the slave(s) for READs, what can we use ?

Three MySQL servers, […]

Read more