Webservers & Caches

Webservers & Caches
I’m a graph-diagram-table person. And when someone asks how web servers and caches are mixed, I now have an image to give them!   Now we can visually see how web server interacts with a page cache in apache, nginx & varnish. And how user cache and opcache for PHP are separated by services like ...

Review: Leaseweb Dedicated Servers 1

I’ve been a customer (on and off) of Leaseweb dedicated servers for about 3 years now for their 100tb packages. Over the years, I probably rented about 6 dedicated servers from them with at least one on each of their DC location (US, NL, DE) and currently have two active servers in Netherlands & Germany. ...

Installing the latest PHP (5.4.23 / 5.5.7) on CentOS/RHEL 1

Method 1 – Remi Repo The Remi Repository (famillecollet.com) maintains the newest PHP for CentOS, RHEL, etc. And by newest, I mean newer than all other major repos. All you need to do is install PHP with Remi enabled. As of writing this article, Remi has 5.4.23 for CentOS, RHEL, etc. If you want even ...

Understanding IOWait 4

IOWait definition & properties IOWait (usually labeled %wa in top) is a sub-category of idle (%idle is usually expressed as all idle except defined subcategories), meaning the CPU is not doing anything. Therefore, as long as there is another process that the CPU could be processing, it will do so. Additionally, idle, user, system, iowait, ...

Diagnosing Windows – Sysinternals

I always found it odd that there are actually quite excellent tools made by Microsoft to diagnose issues with Windows but failed to include it with Windows while offering them for free. What am I talking about you ask? I mean Windows Sysinternals. Or you can get the full package by getting Sysinternals Suite. Sysinternals ...