Thursday, April 29, 2010

Countdown To The Terracotta Toolkit Beta

Countdown To The Terracotta Toolkit Beta

Over the last year, Terracotta has launched four great products backed by the snap-in HA and scalability of the Terracotta Server Array: Enterprise Ehcache, BigMemory for Enterprise Ehcache, Web Sessions and Quartz Scheduler. Building these products has left us feeling a bit greedy. In order to free ourselves from this guilt we've created a toolkit that has allowed us to rapidly build these easy-to-use, high-scale/HA products.

The Revolution Begins

So why should we be the only ones who have all the fun. Lots of smart people out there can build clustered caches, frameworks, and tools? So we are creating the Terracotta toolkit and adjacent Terracotta Compatibility Kit. We will be releasing a set of standard parts like highly concurrent distributed maps, clustered evictors, queues, locks, counters, cluster events etc that can be used by anyone so that they might realize their vision of what the developers of the world should use. This kit was built with a few core goals in mind:

  • Ease of use is paramount - For both the developers that leverage the Terracotta toolkit and the people who use the stuff built using the Terracotta toolkit
  • Stable API matters - We are building a compatibility kit and will maintain a strict and clear versioning scheme so that framework developers can rely on and clearly know what versions of Terracotta can work with the API version used in the application. Your users can just drop in any version of the terracotta-toolkit.jar that implements the version of the API you coded against.
  • Parts is Parts - Get all the useful parts we use to build our products packaged and out for others to use.
  • Scale Continuum - The parts should work both clustered and unclustered continuing our vision of a scale continuum.
The beta of this toolkit is a few short weeks away and we can't wait to see what great stuff people will build on it. Come show us how a cache should be built, come show us what tools we haven't even thought of.

With this toolkit pretty much any framework developer will be able to build out their HA, distributed and scale out dreams.

Monday, April 26, 2010

Dave Klein's Scale Grails Webinar

As someone who spent years in the Smalltalk world I have a special place in my heart for powerful/flexible frameworks and languages that strive for simplicity for the developer. Grails is one of the most powerful and flexible frameworks around and modern representation of those Smalltak values. Some would argue that it's only major missing features are scale-out and HA. The great news on that front is that Grails is built on Quartz, Ehcache, Http Sessions and Hibernate all of which can be scaled with Terracotta in a couple lines of config each. By scaling these four frameworks you can completely scale Grails.

Check out this webinar from the guy who wrote the book on Grails Dave Klein and and learn about it for yourself:

Thursday, April 22, 2010

<terracotta clustered="true"/>

One challenge with drastically simplifying Terracotta as a tool for application scale is getting the word out that it's occurred!

The subject of this blog is one of two lines of config and a jar on the classpath that move Ehcache to be a coherent distributed cache. The line of config in the subject says, "Hey, cluster this cache." The other line, which looks something like this:

"<terracottaConfig url="localhost:9510" />"

tells Ehcache where to find the Server Array.

This same story is true for scaling out Http Sessions, Quartz Scheduling and Hibernate Caching. A whole new world of scale is available to the applications we all write. It free's us from complex sharding, awkward CAP trade offs and endless DB tuning. And the cherry on top is it's open source.

No recompile, no code changes, no magic tricks or additional knowledge. I could train my dog to scale an application built on these ubiquitous frameworks.

Check out these blogs to learn more:

Tuesday, April 20, 2010

Ehcache 2.1 Beta - Lots of Stuff, Still Backward Compatible

UPDATE: 2.1 went GA March 21st

The Ehcache dev team is pretty excited to be getting 2.1 beta out for the world to try. This release is focused on 3 primary goals:
  • Build on our vision of an application scale continuum from one node to the cloud.
  • Improve Ehcache performance both unclustered and clustered.
  • Improve Ehcache applicability for both unclustered and clustered.
What did we do in the name of these goals? Good question!

Scale Continuum

In this release we are focused on taking features that had been added for the Terracotta Clustered version of Ehcache and extending them back to the unclustered version.

The following features fall into that category:
  • The Explicit Locking Module - This module allows you to acquire and release locks manually for given keys. It required some significant rework in the unclustered stores but this now works just as well unclustered as it does clustered supporting fully coherent operations.
  • JTA - In 2.0 of Ehcache we added JTA support when clustered via Terracotta. In 2.1 we extended that functionality to unclustered and have begun the process of performance tuning to go along with its XA compliance.

While performance wasn't a big focus of this release (It is for the next release) we were able to considerably improve Ehcache "put" performance due to the significant work we did on the disk store and locking architecture. We'll also be spending some time tuning JTA but that work did not make it into the beta.


Here we did some considerable work.
  • JTA for Hibernate Second Level Cache - We added support for using Ehcache JTA in a second level cache both clustered and unclustered.
  • UnlockedReadsView - This is a subtle but important feature. For those who are using a coherent cache but have some part of an application that needs to be able to read at high rates without impacting the rest of the cache this view is a huge help.
  • NonStopCache - Useful for guaranteeing that your cache can never stop your application. On a per cache basis an application can avoid holdups caused by problems such as a slow disk in an unclustered cache or a network outage in a clustered one.
  • New Coherent methods - We've added useful methods like putIfAbsent and replace to simply and easily work with a clustered or unclustered cache in a fully coherent manner. Together with the explicit locking wrapper much is possible.
  • We also added a bunch of tests and bug fixes to the web-cache, an extremely useful tool for making performant web applications.
Summing up...

While still in beta we feel like Ehcache 2.1 is another exciting step for our product family. It adds performance, significant features and is still backward compatible. It continues our vision of an application scale continuum from one node to the cloud without burdening the developer with complexity. One set of frameworks, one application, scale out is added at runtime. We are really excited about this vision and are working tirelessly at extending it to all our users' needs.

Please Download Ehcache 2.1 Beta, put it through it's paces and give us lots of feedback!

Monday, April 19, 2010

Application Server Instead Of Web Server

I'm starting to see a small but growing group of sites forgoing web servers and going straight to the Application Server in the Java world. This has some obvious advantages:

  • Less infrastructure
  • Java doesn't have buffer overflows and is a bit more secure
  • You can do much more interesting caching by having the web serving and app serving in the same layer

I was excited to see this blog today and just wanted to point people to it and see what thoughts are out there both pro and con on this trend.