Scaling Java Applications

You have built a Java Application. Now, as the application usage increases, the application needs to be scaled up. The only way to go is scale up (horizontal or vertical). Now the problem is that the application was never built to run in multiple JVM’s. There is no data synchronization, failover, session replication, distributed cache mechanism built in.

Now what can we do. Add more servers( JVM's), but how do we tackle the problem of a common repository for user sessions, transactional data and cache.

This is the need that the following products intend to fulfill.

• Tangosol Coherence
• JBoss Cache
• Gigaspaces
• GemStone
• Terracotta

These products allow you to distribute your data but still making the application believe that their is a single cache and single user sessions repository.