Understanding Size and Performance Limitations
You should carefully plan your Team Foundation Server deployment for the best performance. You should also monitor Team Foundation Server carefully so that you do not run low on system resources. Team Foundation Server might not show many, if any, symptoms before reaching its resource limits. Once those limits have been reached, Team Foundation Server might become unavailable or unstable, and restoring Team Foundation Server to operation will take time and effort.
While there are some minimum resource requirements for Team Foundation Server, planning for optimal resources is not an exact science. Resource needs will vary based on many factors, including number of users, the complexity of the process templates used when creating team projects, the amount of data stored in work items, the complexity of work item types, and so on. You can review the Team Foundation Server Planning Roadmap for information about and links to general system requirements and planning for Team Foundation Server. You should also carefully consider whether a single instance of Team Foundation Server has enough resources before adding a new project. If a Team Foundation Server deployment is running close to the advised limit in number of projects, number of users, or the size of the work item metadata cache, you should consider deploying another Team Foundation Server. For more information, see Team Foundation Server Planning Roadmap and Planning a Team Project.
Understanding Team Project Limits
Overall Team Foundation Server performance does not deteriorate gradually as the number and size of team projects on that Team Foundation Server increases. There will be few symptoms to indicate upcoming problems. It would be easy to overlook those symptoms. For example, Team Foundation clients connecting to that Team Foundation Server for the first time will experience long delays. However, that could be dismissed as the result of a slow network connection. If enough clients attempt a first-time connection to that Team Foundation Server at the same time, the Team Foundation server itself might go over the memory allocation limits in Internet Information Services, which can cause the system to slow or stop. For more information about the factors that determine team project limits and tools to help you determine how to check whether your Team Foundation Server is nearing those limits, see "Team Foundation Server Team Project Limits" on the Microsoft Web site.