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 […]

What is iowait and how does it affect Linux performance?

I/O wait or iowait, wait, wa, %iowait, or wait% is often displayed by command-line Linux system monitoring tools such as top, sar, atop, and others. On its own, it’s one of many performance stats that provide us insight into Linux system performance. I/O wait came up in a recent discussion with a new client. During our […]

Free vs. Available Memory in Linux

At times we will need to know precisely how our Linux systems use memory. This article will examine how to use the free command-line utility to view memory usage on a Linux system. In doing so, we will clearly define the difference between free vs. available memory on Linux systems.   Free vs. Available memory […]

Finding Linux Compatible Printers

Here’s all the info and links needed to find printers or all-in-one printers that currently support Linux. If you don’t want to spend hours comparing printers, have a look at my recommended Linux compatible printers. This is the promised update as per the comments section below, sorry about the delay! Fixed broken manufacture product links and replaced […]

Stop trying to overclock the Raspberry Pi 3 B+

It’s been a while since I’ve written any Raspberry Pi-related posts. Primarily because I’ve been using used $200 to $300 Dell Optiplex Micro computers off eBay, they cost more than the same or less than a Raspberry Pi 3 B+ but can be custom configured with up to 8GB (3050 model), 16GB or 20GB of fast […]

PHP Performance: Additional CPU cores vs Faster CPU cores

Some time ago, I received an email from a client experiencing slow performance issues with a LEMP (Linux, Nginx, MySQL, and PHP webserver). During a full audit, I found that the server’s load average was pretty low (see above screenshot). However, the website was indeed very slow. There were some misconfigurations, but one of the […]

Improving OpenVPN performance and throughput

OpenVPN, Wireguard, L2TP/IPSec, SSTP, IKEv2, PPTP, or others. If you had the luxury of choosing, which VPN protocols would you use? Therein lies my problem. In my current use case, I must find a way to improve OpenVPN performance and throughput. You may have been following my Linux home lab build. One of the most […]

PHP 8 Compatibility Check and Performance Tips.

PHP 7 was first released back on 03 Dec 2015. Yes, it’s been around a while! The PHP team encouraged upgrading to PHP 7, hailing its improvements such as being twice as fast, consistent 64-bit support, removing old and unsupported SAPIs and extensions, and improved fatal error resistance, to name a few. A few years […]

Serving your blog from full-page-cache CDN locations

Ask yourself, would you stick around if this page didn’t load almost immediately, but instead, there was a blank white page for a few seconds? Around half of the internet’s users leave if it takes longer than 2 seconds to load a web page. Two years ago, I used Cloudflare’s Page Rules, specifically the “Cache […]

50 Top ‘Internet of Things’ Security Solutions

A couple of months back, I decided to maintain a list of companies that offer IoT (internet of things) security tools and solutions which you can find below. Feel free to share your solutions, feedback, and tips for securing IoT devices. In the future, I will update this list continuously. A few key questions arose […]