Could not increase number of max_open_files to more than… (Solution)

A quick solution to the warning “Could not increase number of max_open_files to more than” when starting MySQL or MariaDB. For some background read How MySQL Opens and Closes Tables. Here’s an excerpt: “The table_open_cache and max_connections system variables affect the maximum number of files the server keeps open. If you increase one or both of these […]

Tuning MySQL: my.cnf, avoid this common pitfall!

Caution: Don’t overwrite my.cnf all at once. Backup data and config, make one or two changes per restart, test extensively. It took me some time to decide the title for this article. MariaDB has been fast replacing MySQL as a growing number of Linux distributions now default to MariaDB over MySQL. MariaDB is an enhanced drop-in replacement […]

100 Server and Application Performance Monitoring Tools

Last Updated: November 29th 2018 – Site24x7 replaces Coscale. Coscale was recently acquired by New Relic.  Oct 11th 2018 update: 100+ – Fixed 11 broken links. (including defunct, mergers, acquisitions, or changed links) December 1st 2017 update: 70 100 Top Server Monitoring & Application Performance Monitoring Tools. August 6th 2017 update: 50 70 Top Server Monitoring & Application Performance Monitoring Tools. Back in 2014, I […]

20 Top Server Monitoring & Application Performance Monitoring Solutions

UPDATE: 50 Top Server Monitoring & Application Performance Monitoring (APM) Solutions Last Updated: Nov 23th 2018 – Fixed broken links. (including defunct, mergers, acquisitions, or changed links) Back in September I wrote about an article than touched on the subject of server performance monitoring.  Then just last month a LinkedIn connection asked: “I am using New Relic to monitor […]

MySQL Query Cache for Performance, Avoid This When Tuning

Update: MySQL query cache is deprecated as of MySQL 5.7.20, and is removed in MySQL 8.0. – mysql.com One of the most misconfigured MySQL performance features, is MySQL query_cache_size. This post references a web server with 32 gigabytes of RAM where the existing config had MySQL’s query cache size set incorrectly to 4 gigabytes. The thought behind it seemed […]

MySQL Performance: Stop hoarding. Drop unused MySQL databases

Last year, I was assisting a new client in addressing MySQL performance issues. There were several areas where MySQL performance issues were addressed. One issue overlooked for several years prior to our communications, was that of keeping around unused databases. Over 15GB of unused MySQL data – a mix of MyISAM and Innodb tables – […]

Linux server performance: Is disk I/O slowing your application?

This post is sponsored by Instrumental – hosted application and server monitoring with free development accounts. If your Linux server is bogged down, your first step is often to use the TOP command in terminal to check load averages and wisely so. However, there are times when TOP shows very high load averages even with low cpu ‘us’ (user) and high […]

MySQL Performance Tuning: Tips, Scripts and Tools

With MySQL, common configuration mistakes can cause serious performance problems. In fact, if you mis-configure just one of the many config parameters, it can cripple performance! (see examples) Of course, the performance of MySQL is often tied greatly to the efficiency of your MySQL queries. It’s important to ensure that your performance issues are not […]

Memcache PHP Extensions for Memcached Caching Daemon

Memcached (Memcache Daemon) is a caching daemon designed especially for dynamic web applications to decrease database load by storing objects in memory. It is commonly used to speed up dynamic database-driven websites by caching data and objects in server memory to reduce the number of times the data source must be read. Memcached is free and open-source software, […]