Aehso’s Output

With the ever growing trend towards online applications and services, software architects need to be more aware than ever of the challenges in building platforms to host these types of applications. Successful sites in this space (Craigslist, Fickr, Salesforce etc.) all have one common problem to cope with – how do you maintain availability while dealing with exponential audience growth?

Two excellent pieces serve to proffer incredible insight into the experiences of those who have hyper-succeeded in the past:

• Inside MySpace.com, by Baseline Magazine is a great read about how MySpace scaled their architecture from zero to over 26 million user accounts, serving over 40 billion pages a month (isn’t that figure just incredible!).
• Database War Stories is a series of posts by Tim O’Reilly, interviewing folks from Second Life, Memeorandum, Craigslist and more. (The rest of the posts are linked to at the bottom of the first post.)

One common theme in many of these stories: periodically these guys are faced with the stark reality that incremental improvements to existing infrastructure will not sustain the current business model. It is testimony to the folks in charge that they trust their geeks enough to bet the company repeatedly on new architectures.

It is a high-risk world and there are many that fall by the wayside but the rewards for the brave are there for all to see.

aehso dev, hardware, soa, software, web services, web2.0

The N9/N10 Kilcullen – Waterford Road Scheme site should be of interest to anyone living in the sunny south east of Ireland (useful maps). Wexford and Waterford folks might also be interested in online details of the Gorey, New Ross and Waterford bypasses. (Note: to Tramore House: get a web site designer who knows more about usability and less about mouseOver events)

So we will soon have two quality corridors to use to get out of Dublin, nice to have the choice when contributing to our escalating national carbon emission levels. My home town, Borris, is nestled between both routes so its residents should benefit somewhat from both schemes.

Anyone living in the rest of the country can look at the NRA’s Publications/Resources page to find your nearest bypass/toll road development…

aehso irish

It’s a relative thing really, expense: The Telegraph is reporting

Four flats overlooking Hyde Park are on sale for a rumoured £84 million each, the highest price ever asked for a British flat
…..
The complex will also have a spa, squash court and private wine-tasting facility.

The wine-tasting facility is probably the clincher for any prospective purchaser really. That and the prospect of having an arms dealer living next door…

(via BldBlog)

aehso irish, money, property, wayoutthere

A very naive entrepreneur (or a joke) on GetACoder.com:

So I’m posting for a rather large project. I need someone to program me a new OS (Operasting System) that looks different than Ms Windows XP etc. but has the same style. It does not need to run on a mac but all the other PCs. It’s supposed to have a stylish look with clear edges etc. And ITS NOT SUPPOSED TO BE JUST A REDESIGNED WINDOWS as I’m going to sell that operating system later on. It’s going to be called BlueOrb.

The mix of responses is great. Some are hilarious (“My blue orbs will beat your blue orbs”) but are others really taking this seriously (“Well I already designed and OS for Computational chemistry research group…”)?

The mere presence of serious responses, while extreme examples, does show why even attempting to rent coders for anything more than a you-absolutely-couldn’t-possibly-screw-this-up-if-you-tried project is just A Bad Idea.

aehso dev, dumb, junk

Some interesting recent developments in the Web Service space that I’ve been meaning to point to:

• JAX-WS 2.1 has been released.  Enter the tubes…
• BPEL 2.0 is now almost an official OASIS standard.  Do we now have to start referring to it as WS-BPEL instead of plain old BPEL/BPEL4WS?

Only slightly related, some interesting Java WS stacks benchmarks:

• Axis2 vs XFire, published by WSO2.  (with interesting follow-up from Hani and retort from Sanjiva Weerawarana).
• JAX-WS 2.1+JAXB vs Axis2.1.1+XMLBeans, published by Sun.

aehso java, web services

There used to be an age-old restriction in Eclipse whereby two projects couldn’t be imported into the same workspace if the project locations overlapped in the file system. So if you had a project hierarchy like

Then you couldn’t have a workspace that looked like this:

I say ‘age-old’, because (obviously) somewhere along the line this workspace restriction was removed, maybe at the behest of WTP – I’m not sure, I can’t find the related Bugzilla entry (UPDATED: John Arthorne has indirectly pointed me to it – Bugzilla 44967). I only noticed last night when I was just about to blog about how nice it would be to be able to do this. It would appear I am very stuck in my ways – until now I’ve always used separate workspaces to work on the my top level projects and that doesn’t sit too well with trying to use Mylar.

By top level projects I mean a simple project (with no builders/natures) that contain the Ant/PDE build scripts and multiple sub folders, each containing a set of projects (plugin or plain Java) that represent the modular components of our products. These projects are usually big, whole CVS modules in fact, but by synchronizing them with our CVS repository we can easily detect build script changes that might require us to do a little more than re-build each plugin project in our workspaces in order to pick up all of the latest changes.

There is one trick to using this arrangement. Always make sure that you put at least one non-project folder in between your top level project and the contained projects. That way you can check out the top level project, and then point the Eclipse Import “Existing Projects…” wizard at the intermediate folder and it can auto-import all projects found in sub-folders. If you point it at the top level project it will do nothing, thinking you already have that project in your workspace.

Anyway, this is all great good news for anyone who wants to use Mylar with a project arrangement like this since it means that if you need to tweak build scripts as well as plugin source code (which I very frequently do), then you can do it all in one workspace and Mylar will keep track of everything you are doing . This is great for building change sets, especially so for committing changes back to CVS!

There is one caveat though, but only if you check your projects out into your workspace folder folder and I think a lot of people do this. If you try to subsequently use the New Project wizard to try create a “contained” project (like the ‘inner’ one illustrated above) then you will hit a problem. When you deselect the “Use default location” check box for the second (contained) project, the wizard will flag an error claiming that the “Project contents cannot be inside workspace directory”. I have no idea why it does this since this the suggested default is in the workspace folder but it’d be nice if the platform guys could fix this. It must be a trivial fix, I’m guessing it’s doing an indiscriminate “location.startsWith()” validation check on the string or something (see Bugzilla 165336. (UPDATE 2: it looks like the UI bug is fixed for 3.3 – see Bugzilla 147727)

A workaround is to create the project elsewhere, delete it from the workspace (but not it’s contents), move it on the filesystem and then re-import it into the workspace…

aehso dev, eclipse