Application Server Sizing

Application servers do not typically consume a large amount of server resources in the Simphony platform. Database servers are where most of the I/O and CPU/RAM usage occurs. That being said, application servers still need to be configured with the proper resources to handle the workload, primarily through IIS and various other Simphony web services. Oracle Hospitality recommends that customers operate all of the web services which are capable of being load balanced on every application server and to place a load balancer (either a software load balancer or a hardware device) in front of the application servers to distribute the load. It is also possible to dedicate individual servers to do some, or even individual jobs needed by the application. For example, a single server, or even multiple servers that only run the Direct Posting Service. Servers that run only the EGateway service and no other services. This all depends on the requirements of the enterprise and how the customer wants to distribute the application load. The inherent extensibility and both the horizontal and vertical scalability of the architecture allow infinite combinations of services to meet the needs of an enterprise only limited by the hardware available (both real and virtual).

As for disk sizing, the only growth items on an application server are the log files when it comes to the Simphony application. The Simphony application itself is not very I/O intensive on the disk side of the hardware. The size of the enterprise does not impact the disk usage to the point where different recommendations must be made for larger customers.

RAM is a crucial resource. RAM requirements for large enterprises are where the application servers can greatly vary, based primarily upon the number of menu items and employees configured in the system. The application server caches data for use by the EMC and Database Download Handlers. The cached data is used to speed up the performance of the system in those applications. Other processes such as the posting handler, Data Transfer Service (DTS) and Direct Posting Service (DPS) also require RAM.

Since application servers are load balanced, it is possible for a request for any of the processes to come to an application server, it is necessary to load the servers with enough RAM to handle everything on all of the servers; or as mentioned above, to split the application servers even further into even more specialized servers that handle specific tasks within the enterprise. When deciding upon how much memory to put into an application server, it is important to consider what the operating system is actually capable of supporting.