Infinispan as a LOCAL cache

While Infinispan has got the distributed, in-memory data grid market firmly it in its sight, there is also another aspect of Infinispan which I feel people would find interesting.

At its heart Infinispan is a highly concurrent, extremely performant data structure than can be distributed, or could be used in a standalone, local mode - as a cache. But why would people use Infinispan over, say, a ConcurrentHashMap? Here are some reasons.

Feature-rich

• Eviction. Built-in eviction ensures you don't run out of memory.
• Write-through and write-behind caching. Going beyond memory and onto disk (or any other pluggable CacheStore) means that your state survives restarts, and preloaded hot caches can be configured.
• JTA support and XA compliance. Participate in ongoing transactions with any JTA-compliant transaction manager.
• MVCC-based concurrency. Highly optimized for fast, non-blocking readers.
• Manageability. Simple JMX or rich GUI management console via JOPR, you have a choice.
• Not just for the JVM. RESTful API, and upcoming client/server modules speaking Memcached and HotRod protocols help non-JVM platforms use Infinispan.
• Cluster-ready. Should the need arise.

Easy to configure, easy to use

The simplest configuration file containing just

<infinispan />

is enough to get you started, with sensible defaults abound. (More detailed documentation is also available).

All the features above are exposed via an easy-to-use Cache interface, which extends ConcurrentMap and is compatible with many other cache systems. Infinispan even ships with migration tools to help you move off other cache solutions onto Infinispan, whether you need a cache to store data retrieved remotely or simply as a 2nd level cache for Hibernate.

Performance

In the process of testing and tuning Infinispan on very large clusters, we have started to put together a benchmarking framework. As a part of this framework, we have the ability to measure cache performance in standalone, local mode. So in the context of this blog post, I'd

like to share some recent performance numbers of Infinispan - a recent snapshot - compared against the latest JBoss Cache release (3.2.2.GA) and EHCache (1.7.2). Some background on the tests:

• Used a latest snapshot of the CacheBenchFwk
• Run on a RHEL 5 server with 4 Intel Xeon cores, 4GB of RAM
• Sun JDK 1.6.0_18, with -Xms1g -Xmx1g
• Test run on a single node, with 25 concurrent threads, using randomly generated Strings as keys and values and a 1kb payload for each entry, with a 80/20 read/write ratio.
• Performance measured in transactions per second (higher = better).

In summary, what we have here is that when run in local mode, Infinispan is a high-performance standalone caching engine which offers a rich set of features while still being trivially simple to configure and use.

Enjoy,

Manik

Infinispan Query breaks into 4.0.0.CR1

Hello all,

Querying is an important feature for Infinispan, so we've decided to include a technology preview of this for 4.0.0.CR1 and 4.0.0.GA, even though it is only really scheduled for Infinispan 4.1.0.

Browse to this wiki page to see how the new API works for querying, along with usage examples.

Origins
Some of the API has come from JBoss Cache Searchable but has been enhanced and runs slicker. A lot more work is being done under the hood so it makes it easier for users. For example, the API method on the QueryFactory.getBasicQuery() just needs two Strings and builds a basic Lucene Query instance, as opposed to forcing the user to create a Lucene query manually. This is still possible however, should a user want to create a more complex query.

The indexing for Lucene is now done through interceptors as opposed to listeners, and hence more tightly integrated into Infinispan's core.

You can also choose how indexes are maintained. If indexes are shared (perhaps stored on a network mounted drive), then you only want nodes to index changes made locally. On the other hand, if each node maintains its own indexes (either in-memory on on a local filesystem) then you want each node to index changes made, regardless of where the changes are made. This behaviour is controlled by a system property - -Dinfinispan.query.indexLocalOnly=true. However, this is system property temporary and will be replaced with a proper configuration property once the feature is out of technology preview.

What's coming up?
Future releases of Hibernate Search and Infinispan will have improvements that will change the way that querying works. The QueryHelper class - as documented in the wiki - is temporary so that will eventually be removed, as you will not need to provide the class definitions of the types you wish to index upfront. We will be able to detect this on the fly (see HSEARCH-397)

There will be a better system for running distributed queries. And the system properties will disappear in favour of proper configuration attributes.

And also, GSoC student Lukasz Moren's work involving an Infinispan-based Lucene Directory implementation will allow indexes to be shared cluster-wide by using Infinispan itself to distribute these indexes. All very clever stuff.

Thanks for reading!

Navin.

Comparing JBoss Cache, Infinispan and Gigaspaces

Chris Wilk has posted a detailed blog comparing features in JBoss Cache, Infinispan and Gigaspaces.

This well-written article is available here:

http://bigdatamatters.com/bigdatamatters/2009/09/infinispan-vs-gigaspaces.html

and is a good starting point for more in-depth analysis and comparison.

Cheers

Manik