Like many people, you probably have questions about planning a solid K2 deployment. You don't want to underplan for a deployment by not taking into account the different moving parts that make up K2. And it's easy to become overwhelmed by looking at the architecture diagrams and listing out all the different services, databases, and integration points. You may wonder how scalable K2 is, can it run on one box, can it scale, and even how does it scale? The answer is always the same: It depends.
While K2 has much in common with many other three-tier applications, it is also different. It is different in that the workload profile can change dramatically from customer to customer and even from process to process. Some customers may use SharePoint; some may not; some may use ASP.NET forms, and some may use InfoPath. Some may use K2 to integrate with many back-end systems; some may not integrate it at all. There are too many variables to accurately predict, with any degree of certainty, a formula for how to scale.
While the architecture of K2 does correlate to a normal three-tier server application, it also differs in that the tiers can vary.
The front tier can be Web forms, InfoPath forms services, SharePoint, or virtually anything you can imagine. The application tier is the K2 server along with its ancillary services, such as SmartObjects interfaces and the Web services for SharePoint. The data layer is the set of K2 SQL Server databases. ...