dan/blog

We setup our Rackspace Cloud account for internal development today and it is nice…

Amazon Web Services

We’ve been using Amazon Web Services for a few years now, and I still really like what they have to offer, but it must be said that Rackspace have thought about making things cuddly. Before we got into AWS, we were using Rackspace for dedicated hosting but never go around to trying their cloud hosting because…. well, just too busy.

Then they asked us to build their website for them and gave us some lovely VMs and access to Cloud Files.

The interfaces Rackspace have made are nice than those Amazon provide, in my opinion, but it’s worth thinking about why. Amazon went into cloud computing thinking they’d be the British Sugar of the industry: sell the fundamental commodity, encourage an ecosystem around them and bring in the popular and proven. Nice.

Rackspace are all about support, so you might be reselling their services but as far as they’re concerned you’re the end user, and you feel it.

Anyway… first day so let’s see how it goes.

I’ve found recently that complex designs aren’t just more difficult to build, but have significant effects on browser performance. To improve the performance of our site, we used CDN (Amazon S3 hosting the files), we removed background images and we tweaked the server configuration no end.

Now, something you find out very soon when you start optimising pages is that your browser can’t make more than 2 requests to a given domain at any time. So, when you hits Amazon.com we get the HTML, then we connect back to amazon.com to get the CSS, images and JavaScript to make the page pretty and clever. These extra bits – collectively called resources – can only be downloaded 2 at a time from a given domain name.

This matters because your beautiful page, with its drop-shadows, fancy JavaScript and massive background image all needs to be downloaded before the user can enjoy just how lovely it is. BUT… if you have 10 images sitting on 1 server your browser can only get 2 at a time. This slows things down.

Part of the answer is a CDN – a content delivery network – whose sole role is to host resources on a different domain from your website. So the images for example.com might be hosted on static.example.com, or even on static1.example.com, static2.example.com and static3.example.com. The more domains, the more connections your browser can make.

You can also read a very good description of implementing a CDN with Rackspace’s Cloud services.

So, that’s method number one. Another method is to reduce the number of resources that have to be downloaded. Instead of downloading 100 images, download 2. Google Web Toolkit does this out of the box, by bundling up individual images for you.

A rails package I just came across does the same thing – check out http://documentcloud.github.com/jammit/ mentioned in Rails Inside.

Once again, something that isn’t new but is really valuable.

Grady Booch on Architecture is worth listening to for some architecture wisdom.

Not only is Google convinced it can build browsers better than other people, it now seems to think that browsers shouldn’t even visit websites at all.

Read the rest of this entry »

The internet, 2003

Wasn’t the internet busy in 2003. Taken from New Scientist. Old, I know. But if you look carefully you can see where I was ssh’ing to a server in Germany… just near the blue line.

Coders are rubbish at testing. QS, UAT, and Testers all just add entropy.

Very good article over at Google Testing blog: http://googletesting.blogspot.com/2009/09/plague-of-entropy.html

Recently featured on the AWS Blog, Twilio provides an API to phone calls. When someone calls in, it fires a web service on your server. You can then respond with a message – e.g. “Thanks for calling” – which is spoken back to the caller.

I particularly like this kind of cloud app because it is a bridge to a domain to which web developers tends not to have access at the moment.

Now I just need to contrive a project to use Twilio.

Doing research for my what’s-new-in-GWT article for Linux Magazine (http://www.linux-magazine.com/).

This isn’t new, but worth knowing about. A GWT app written for the iPhone when it first came out.

http://gwt.google.com/samples/GwtFeedReader/GwtFeedReader.html