In the previous episodes of this serie , we’ve addressed the availability , scalability and Performances aspects of HA Architecture. In this one we’ll concentrate on the future of these architectures and the emerging technologies to tackle specific HA constraints.
The future is a G word : GRID. Grid of memory, grid of CPU and Grid of disks. The main limitations today is to have this one to one relationship between the application and the physical server on which the former is deployed. Hence the main trend of the market today : to virtualize servers by using Network Access processing, memory and storage.
Network Accessed processing
This is the Grid of CPUs. Azul Systems offers some sort of Java mainframe, a box containing 768 CPUs and 700GO of memory. Applications are deployed on blades as usual but these blades contain a proxy to the Azul box : whenever CPU process is required, the blade proxy hands it over to the Azul box which is configured to allocate a certain number of CPUs for that very app.
Websphere XD also offers new possibility on CPU and servers virtualization.
Network Accessed Memory
Terracotta offers a solution for Network Accessed Memory. This is a server managing objects lying in network memory. Thus differents applications running on different JVMs and different servers can share the same instance of a given object. Client applications just need to import the terracotta client libs and define in a description XML file the objects and attributes to be shared and that’s it !
Main issue here with the open source version : 2mn start up time. This would then create a main Single Point Of Failure in the system.
Network Access Storage
SAN (Storage Access Network) offers a very robust and efficient solution for network repository. Communication are fiber channel based and therefore very performant .. but very expensive. This already is commonly used and it has paved the way for the above 2 other solutions of network access services.