performance

On a recent project, there was a Migration run that took a very long time, and I couldn't pinpoint why; there were multiple migrations, and none of the others took very long at all (usually processing at least hundreds if not thousands of nodes per minute). In Drupal 7, if you enabled the XHProf module, then you'd get a checkbox on the configuration page that would turn on profiling for all page requests and Drush commands.

In Drupal 8, the XHProf module was completely rewritten, and as a side effect, the Drush/CLI profiling functionality is not yet present (see: Profile drush/CLI with XHProf in Drupal 8).

Since I don't have the time right now to help figure out how to get things working through the official XHProf module, I decided to use a 'poor man's profiling' method to profile a Migration run:

Recently, I was upgrading the infrastructure for Hosted Apache Solr, and as part of the upgrade, I jumped from Nginx 1.8.x to 1.10.x, which includes HTTP/2 support. I had previously used SPDY support in my server configuration to help the site run better/faster on modern browsers with SPDY support:

After the server upgrades, I was getting the following error on Nginx restarts:

So I switched the configuration to use http2 instead of spdy on the listen line, and restarted nginx.

Everything worked great in Safari and FireFox, but when I tried loading the page in Chrome, I was greeted with the following error:

Drupal VM is one of the most flexible and powerful local development environments for Drupal, but one the main goals of the project is to build a fully-functional Drupal 8 site quickly and easily without doing much setup work. The ideal would be to install Vagrant, clone or download the project, then run vagrant up. A few minutes later, you'd have a Drupal 8 site ready for hacking on!

In the past, you always had to do a couple extra steps in between, configuring a drupal.make.yml file and a config.yml file. Recently, thanks in huge part to Oskar Schöldström's herculean efforts, we achieved that ideal by switching from defaulting to a Drush make-based workflow to a Composer-based workflow (this will come in the 3.1.0 release, very soon!). But it wasn't without trial and tribulation!

tl;dr: Drupal 8's defaults make most Drupal sites perform faster than equivalent Drupal 7 sites, so be wary of benchmarks which tell you Drupal 7 is faster based solely on installation defaults or raw PHP execution speed. Architectural changes have made Drupal's codebase slightly slower in some ways, but the same changes make the overall experience of using Drupal and browsing a Drupal 8 site much faster.

When some people see reports of Drupal 8 being 'dramatically' slower than Drupal 7, they wonder why, and they also use this performance change as ammunition against some of the major architectural changes that were made during Drupal 8's development cycle.

First, I wanted to give some more concrete data behind why Drupal 8 is slower (specifically, what kinds of things does Drupal 8 do that make it take longer per request than Drupal 7 on an otherwise-identical system), and also why this might or might not make any difference in your choice to upgrade to Drupal 8 sooner rather than later.

Over the past few months, I've been reading about BigPipe, Cache Tags, Dynamic Page Cache, and all the other amazing-sounding new features for performance in Drupal 8. I'm working on a blog post that more comprehensively compares and contrasts Drupal 8's performance with Drupal 7, but that's a topic for another day. In this post, I'll focus on cache tags in Drupal 8, and particularly their use with Varnish to make cached content expiration much easier than it ever was in Drupal 7.

Late last year, I published a blog post with comprehensive benchmarks of various microSD cards used with the internal Raspberry Pi 2 reader, based on the comprehensive (and always-up-to-date Raspberry Pi microSD card benchmark page I maintain for the Pi Dramble project). After publishing the blog post, a few different readers pointed me to some overclocking tweaks that could help boost the speeds further for UHS microSD cards, allowing large file I/O speed to double, and random I/O to get a solid boost as well.

2018 Update: Please see the latest benchmarks in 2018 using a Raspberry Pi model 3 B+.

This post's benchmarks were performed on a Raspberry Pi 2; for all the latest benchmarks, on Raspberry Pi 3 or later revisions, check out the official Pi Dramble microSD card Benchmarks page.

In my experience, one of the highest-impact upgrades you can perform to increase Raspberry Pi performance is to buy the fastest possible microSD card—especially for applications where you need to do a lot of random reads and writes.

[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.

DrupalCamp St. Louis 2015 was held this past weekend, June 20-21, 2015, at SLU LAW in downtown St. Louis. We had nine sessions and a great keynote on Saturday, and a full sprint day on Sunday.

The view coming off the elevators at SLU LAW.

Every session was recorded (slides + audio), and you can view all the sessions online:

• Keynote - Finding the entrance: Why and how to get involved with the Drupal community
• .git basics
• Empowering Content Creators Through Better UX
• Out on a TWIG: custom theme development
• Securing Drupal
• Age of Content: Building Meaningful Content Strategies
• Scale up your Drupal Search
• High Performance Drupal
• Challenges of designing for a CMS
• Status of Migrate in 8
• Closing Session

The Camp went very well, with almost sixty participants this year! We had a great time, learned a lot together, and enjoyed some great views of downtown St. Louis (check out the picture below!), and we can't wait until next year's DrupalCamp St. Louis (to be announced)!

Version 0.9.3 of the Dramble—running Drupal 8 on 6 Raspberry Pis

I've been tinkering with computers since I was a kid, but in the past ten or so years, mainstream computing has become more and more locked down, enclosed, lightweight, and, well, polished. I even wrote a blog post about how, nowadays, most computers are amazing. Long gone are the days when I had to worry about line voltage, IRQ settings, diagnosing bad capacitors, and replacing 40-pin cables that went bad!

But I'm always tempted back into my earlier years of more hardware-oriented hacking when I pull out one of my Raspberry Pi B+/A+ or Arduino Unos. These devices are as raw of modern computers as you can get—requiring you to actual touch the silicone chips and pins to be able to even use the devices. I've been building a temperature monitoring network that's based around a Node.js/Express app using Pis and Arduinos placed around my house. I've also been working a lot lately on a project that incorporates three of my current favorite technologies: The Raspberry Pi 2 model B (just announced earlier this month), Ansible, and Drupal!

In short, I'm building a cluster of Raspberry Pis, and designating it a 'Dramble'—a 'bramble' of Raspberry Pis running Drupal 8.