drupal 8

Always getting X-Drupal-Cache: MISS? Check for messages

I spent about an hour yesterday debugging a Varnish page caching issue. I combed the site configuration and code for anything that might be setting cache to 0 (effectively disabling caching), I checked and re-checked the /admin/config/development/performance settings, verifying the 'Expiration of cached pages' (page_cache_maximum_age) had a non-zero value and that the 'Cache pages for anonymous users' checkbox was checked.

After scratching my head a while, I realized that the headers I was seeing when using curl --head [url] were specified as the defaults in drupal_page_header(), and were triggered any time there was a message displayed on the page (e.g. via drupal_set_message()):

<br />
X-Drupal-Cache: MISS<br />
Expires: Sun, 19 Nov 1978 05:00:00 GMT<br />
Cache-Control: no-cache, must-revalidate, post-check=0, pre-check=0<br />
X-Content-Type-Options: nosniff<br />

Benchmarking PHP 7 vs HHVM - Drupal and Wordpress

[Multiple updates: I've added results for concurrencies of 1 and 10, results on bare metal vs. VMware instances, tested Drupal 8 vs Drupal 7 vs Wordpress 4.4, and I've also retested every single benchmark at least twice! Please make sure you're read through the entire post prior to contesting these benchmark results!]

tl;dr: Always test your own application, and trust, but verify every benchmark you see. PHP 7 is actually faster than HHVM in many cases, neck-in-neck in others, and slightly slower in others. Both PHP 7 and HHVM blow PHP ≤ 5.6 out of the water.

Skip to benchmark results:

Drupal 8 with Redis, PHP 7, Nginx, and MariaDB on Drupal VM using CentOS

One of the motivations behind Drupal VM is flexibility in local development environments. When you develop many different kinds of Drupal sites you need to be able to adapt your environment to the needs of the site—some sites use Memcached and Varnish, others use Solr, and yet others cache data in Redis!

Drupal VM has recently gained much more flexibility in that it now allows configuration options like:

  • Choose either Ubuntu or CentOS as your operating system.
  • Choose either Nginx or Apahe as your webserver.
  • Choose either MySQL or MariaDB for your database.
  • Choose either Memcached or Redis as a caching layer.
  • Add on extra software like Apache Solr, Node.js, Ruby, Varnish, Xhprof, and more.

Out of the box, Drupal VM installs Drupal 8 on Ubuntu 14.04 with PHP 5.6 (the most stable release as of December 2015) and MySQL. We're going to make a few quick changes to config.yml so we can run the following local development stack on top of CentOS 7:

Drupal VM - Drupal 8 status report page showing Nginx, Redis, MariaDB, and PHP 7

Configure Drupal VM

To get started, download or clone a copy of Drupal VM, and follow the Quick Start Guide, but before you run vagrant up (step 2, #6), edit config.yml and make the following changes/additions:

Celebrate Drupal 8 in St. Louis, MO on Nov 19 - Food, Drinks, and a Raspberry Pi!

Drupal 8 Logo

On November 19, the St. Louis Drupal Users Group is having a party to celebrate the release of Drupal 8, which has been 4 years in the making! The party will be hosted at Spry Digital in downtown St. Louis, and will have beer provided by Manifest, food and drinks provided by Spry, and a Raspberry Pi 2 model B giveaway sponsored by Midwestern Mac!

Drupal 8.0.0 has been built by over 3,000 contributors in all corners of the globe, and will help kick off the next generation of personalized, content-driven websites. During the meetup, we'll build a brand new Drupal 8 site on the Raspberry Pi using Jeff Geerling's Drupal Pi project, and we'll highlight some of the awesome new features of Drupal 8.

Raspberry Pi and Acquia dancing man

After we build one of the first Drupal 8 sites, we'll give away the Raspberry Pi to a lucky winner to take home and tinker with! Special thanks to the Austin Drupal Users Group, who came up with the Pi giveaway idea!

We'll also eat, drink and be merry, celebrating the start of a new era of site building with the best version of Drupal yet!

If you'd like to join us, please RSVP on the STLDUG Meetup page: STLDUG Drupal 8.0.0 Release Party.

Drupal Pi project featured on Acquia Dev Center Blog

Acquia Raspberry Pi model 2 B

I recently wrote a post detailing how to set up Drupal 8 on a Raspberry Pi using the Drupal Pi project (the same setup which is currently powering www.pidramble.com!) on the Acquia Developer Center blog: Drupal and the Raspberry Pi.

Hopefully people will find more and more useful ways to use Drupal 8 on the Raspberry Pi for automation, for interactivity, and most of all for fun and experimentation!

Vagrant web development - is VMware better than VirtualBox?

[Update 2015-08-25: I reran some of the tests using two different settings in VirtualBox. First, I explicitly set KVM as the paravirtualization mode (it was saved as 'Legacy' by default, due to a bug in VirtualBox 5.0.0), which showed impressive performance improvements, making VirtualBox perform 1.5-2x faster, and bringing some benchmarks to a dead heat with VMware Fusion. I also set the virtual network card to use 'virtio' instead of emulating an Intel PRO/1000 MT card, but this made little difference in raw network throughput or any other benchmarks.]

My Mac spends the majority of the day running at between one and a dozen VMs. I do all my development (besides iOS or Mac dev) running code inside VMs, and for many years I used VirtualBox, a free virtualization tool, along with Vagrant and Ansible, to build and manage all these VMs.

Launching my first Drupal 8 website — in my basement!

I've been working with Drupal 8 for a long time, keeping Honeypot and some other modules up to date, and doing some dry-runs of migrating a few smaller sites from Drupal 7 to Drupal 8, just to hone my D8 familiarity.

Raspberry Pi Dramble Drupal 8 Website

I finally launched a 'for real' Drupal 8 site, which is currently running on Drupal 8 HEAD—on a cluster of Raspberry Pi 2 computers in my basement! You can view the site at http://www.pidramble.com/, and I've already started posting some articles about running Drupal 8 on the servers, how I built the cluster, some of the limitations of at-home webhosting, etc.

Some of the things I've already learned from building and running this cluster for the past few days:

Nginx Load Balancer Visualization on a Raspberry Pi Cluster

After some more tinkering with the Raspberry Pi Dramble (a cluster of 6 Raspberry Pis used to demonstrate Drupal 8 deployments using Ansible), I finally was able to get the RGB LEDs to react to Nginx accesses—meaning every time a request is received by Nginx, the LED toggles to red momentarily.

This visualization allows me to see exactly how Nginx is distributing requests among the servers in different load balancer configurations. The default (not only for Nginx, but also for Varnish, HAProxy, and other balancers) is to use round-robin distribution, meaning each request is sent to the next server. This is demonstrated first, in the video below, followed by a demonstration of Nginx's ip_hash method, which pins one person's IP address to one backend server, based on a hash of the person's IP address:

Major improvements to Drupal VM - PHP 7, MariaDB, Multi-OS

Drupal VM - Vagrant and Ansible Virtual Machine for Drupal Development

For the past couple years, I've been building Drupal VM to be an extremely-tunable, highly-performant, super-simple development environment. Since MidCamp earlier this year, the project has really taken off, with almost 200 stars on GitHub and a ton of great contributions and ideas for improvement (some implemented, others rejected).

In the time since I wrote Developing for Drupal with Vagrant and VMs, I've focused on meeting all my defined criteria for the perfect local development environment. And now, I'm able to say that I use Drupal VM when developing all my projects—as it is now flexible and fast enough to emulate any production environment I use for various Drupal projects.

Ansible for Drupal infrastructure and deployments - DrupalCon LA 2015 BoF

We had a great discussion about how different companies and individuals are using Ansible for Drupal infrastructure management and deployments at DrupalCon LA, and I wanted to post some slides from my (short) intro to Ansible presentation here, as well as a few notes from the presentation.

The slides are below:

And video/audio from the BoF:

Notes from the BoF

If first gave an overview of the basics of Ansible, demonstrating some Ad-Hoc commands on my Raspberry Pi Dramble (a cluster of six Raspberry Pi 2 computers running Drupal 8), then we dove headfirst into a great conversation about Ansible and Drupal.