In June 2021, Google factors your page speed into your search ranking score for computing your Google Page Rank. Your website’s speed is not only important to your users, but also to Google. Google factors your page speed into your search ranking score and in June will rely on it…

Online and flexible learning options were already key to universities’ long-term growth strategies. Higher-ed was already experimenting heavily in hybrid and completely online learning before Covid-19, with extensive investment in edtech leading development both in terms of curriculum and technology. For universities and educational institutions, sustainability and long-term usability and…

Here’s what you should be doing in your Varnish setup. Do these things in Varnish! 1. Use Varnish’s shared memory logging Varnish has some powerful logging abilities (VSL — Varnish SharedLog) that can provide a lot of troubleshooting and performance insight. Our webinar hosts have both written about shared memory logging in the past: I wrote about it in the Varnish…

Here is some guidance for Varnish users to help them get the maximum performance and efficiency from their Varnish setups. — 1. Don’t set your time to live (TTL) to zero It seems counterintuitive. If you don’t want to cache your content, doesn’t it seem like it makes sense to give the content a null TTL? However, do not set your TTL to zero. This is really important. Keep in mind that if you set a 0 TTL, you’re instructing Varnish…

The single most frequent question we get from people discovering Varnish is “Do you support request collapsing?”. And admittedly, it always catches us off guard, because of course, it has been doing so for years, and it’s a caching server, so that’s a must-have, right? (Yes, yes it is.) For…

You probably already know that we love the VCL (Varnish Configuration Language) idea, big time. Being able to change the processing logic via code opens a world of possibilities and makes pretty much all other tools feel constrained in their configurations. But… But, well, VCL is code, and code is…

First of all, these timeouts are Varnish Cache parameters. This means that they are global to all requests and backend connections, and are either set on startup or runtime via `varnishadm`. If you for example want to increase timeout_req to 5 seconds, you can either add “-p timeout_req=5” to the…

In this post I will shed some light on Varnish Cache memory usage. In particular, we will examine the malloc storage backend and tune jemalloc for optimal usage. Storage Backends First, let’s review how Varnish Cache actually stores its content. Varnish Cache stores content in pluggable modules called storage backends. It does…

Although the Varnish Book covers all Varnish-related things, we’ve gathered the most common Varnish Cache mistakes and are addressing these in this short tutorial. — UPDATE: this post has been around for quite some time already and some items have become outdated. To address this we’re hosting a webinar on the same topic. Caching set cookies Caching an object with a Set-Cookie header can have devastating effects, as any client requesting the object will get…