A Fantastic Set Of Web Development Analysis Tools

UItest.com have pulled together a fantastic set of links to all sorts of web standards and performance tests. Well done guys!

Useful Free Web Tools For W3C Contrast Compliance

Here are a couple of very useful web based tools for checking W3C compliance.

The first by Johnathan Snook enables you to check the colour contrasts of your theme for W3C compliance when viewed by someone having color deficits or when viewed on a black and white screen. The tool will indicate that the colours pass the test if both the colour difference and the brightness difference exceed their threshold. It will indicate that it sort of passes if only one of the two values exceed their threshold. And finally, it'll fail to pass if neither value exceeds its threshold.

The tool will also indicate if the colours pass the newer WCAG 2.0 contrast ratio formula. The WCAG 2.0 formula differentiates between text smaller than 18pt text larger than 18pt (or text that is bold and larger than 14pt). For AA compliance, text should have a ratio of at least 4.5:1 (larger text, at least 3:1). For AAA compliance, text should have a ratio of at least 7:1 (larger text, at least 4.5:1).

The second by Juicy Studio enables you to check your CSS for validity against the W3C's validation service, along with a colour contrast test, and a test to ensure that relevant sizes are specified in relative units of measurement.

Funny Indian Airlines TV Advert

I found this on the XO Blog, made my chuckle so that I'd share :)

Google Maps In Your Audi

Google & Audi have announced they will collaborate to build a Androide based saterlite navigation system into the R8.  Drivers will be presented with 3D satellite imagery, terrain information, and a variety of locational points augmented with useful data such as Wikipedia entries. It doesn't end at the car interior though, Audi A8 drivers will be able to search and send business directories and addresses from the office desktop computer prior to actually getting in front of the wheel.  More....

extreme transaction processing patterns and write behind caching

Below is the intro to a great article by Lan Vuong posted on InfoQ about extreme transaction processing patterns and write behind database caching.

Applications typically use a data cache to increase performance, especially where the application predominantly uses read-only transactions. These applications directly update the database for changes in the data. The issue here is that as the load increases then the response time on these updates grows. Databases are not good at executing lots of concurrent transactions with a small number of records per transaction. Databases are much better at executing batched transactions.

Eventually, the database will saturate the CPU or disks and at that point the response time will rise as additional load is added. Conventional in-memory caches are also limited to only storing what can fit in the free memory of a JVM. Once we need to cache more than this amount of data then thrashing occurs where the cache continuously evicts data to make room for other data. The required record must then be read continually thereby making the cache useless and exposing the database to the full read load.

There are several products currently available, including IBM® WebSphere® eXtreme Scale, Oracle Coherence, and Gigaspaces that allow all of the free memory of a cluster of JVMs to be used as a cache rather than just the free memory of a single JVM. This allows the capacity of the cache to scale as more JVMs are incorporated. If these JVMs are on additional physical servers with CPU, memory and network, then this allows scalable servicing of read requests. They can also provide scalable servicing of update requests by leveraging their write-behind technology. The scalability of write-behind caching makes it ideal to handle extreme transaction processing (XTP) scenarios. XTP is defined by Gartner as "an application style aimed at supporting the design, development, deployment, management and maintenance of distributed TP applications characterized by exceptionally demanding performance, scalability, availability, security, manageability and dependability requirements.”

In this paper, we will illustrate how to optimize the performance of an application by leveraging the write-behind pattern with examples using IBM WebSphere eXtreme Scale. The write-behind function batches updates to the back-end database asynchronously within a user configurable interval of time. The obvious advantage of this scenario is reduced database calls and therefore reduced transaction load and faster access to objects in the grid. This scenario also has faster response times than the write-through caching scenario where an update to the cache results in an immediate update to the database. In the write-behind case, transactions no longer have to wait for the database write operation to finish. Additionally, it protects the application from database failure as the write-behind buffer will hold changes through memory replication until it can propagate them to the database. more....

Performance profile your web pages with Speedtracer for Chrome

Speed Tracer is a tool to help you identify and fix performance problems in your web applications. It visualizes metrics that are taken from low level instrumentation points inside of the browser and analyzes them as your application runs. Speed Tracer is available as a Chrome extension and works on all platforms where extensions are currently supported (Windows and Linux).
Using Speed Tracer you are able to get a better picture of where time is being spent in your application. This includes problems caused by JavaScript parsing and execution, layout, CSS style recalculation and selector matching, DOM event handling, network resource loading, timer fires, XMLHttpRequest callbacks, painting, and more.  Learn more and download at.....

Google Chrome for Mac is finally here

Google Chrome for Windows has been around for a while now and has been building a steady following based on it's lighting fast speed in comparison to IE.  Now Google have launched an 'official' Mac OSX version although only for Intel based machines.  It appears to only be a cut down version and a little flacky but Google say they will release a further 'stable' beta in January.  Download....

Build your Flex applications natively for multiple mobile platforms

ELIPS Studio3, winners of the OSEO prize at the Deloitte Technology Fast50 2009 launches free beta program. Looks like it should be worth signing up...........


Mobile Application Development in Flex Builder!  ELIPS Studio 3 is a plug-in for Adobe Flex Builder, a widely used IDE for internet & desktop application. Our plug-in allows Flex to go mobile!

Use services from our Mobile Flex FrameworkThe product offers a mobile-optimized Flex Framework, plus numerous Flex extensions, including mobile UI components & access to mobile device features (voice call, SMS, access to calendar and contacts, to the camera, etc.)

Build for the Mobile Platform you wantELIPS Studio 3 is based on a native runtime.

It will automatically generate, optimize and package your Flex applications as native code for industry-leading platforms, including iPhone, Windows Mobile, Symbian, Android, etc. One code base for all platforms... and unforeseen performances!

Clay Shirky talking at TED about Social Media

Well worth a watch for a in-depth analysis of the topic

What makes Google Chrome So Fast

A great series of technical presentations on the three key techniques that haven given Google Chrome it's incredible speed:-

• DNS pre-resolution
• V8 JavaScript engine
• DOM bindings and more