MACROMEDIA COLDFUSION 4.5-ADMINISTRING COLDFUSION SERVER Manual page 153

Chapter 6: Creating Scalable and Highly Available Web Sites
ColdFusion ensures that your Web applications perform well by including many
performance-friendly features out of the box, including:
Just-in-time compiling and client-side caching
ColdFusion automatically compiles pages the first time they are requested in a
session and stores the compiled representations in memory.
Dynamic HTML support
Multi-threaded architecture
Servlet and applet support
Full DBMS support for native drivers, triggers, and stored procedures
Support for distributed computing models, including DCOM and CORBA
Linear scalability
Perfect scalability — excluding cache initializations — is linear. Linear scalability,
relative to load, means that with fixed resources, performance decreases at a constant
rate relative to load increases. Linear scalability, relative to resources, means that with
a constant load, performance improves at a constant rate relative to additional
resources.
Caching and resource management overhead affect an application server's ability to
approach linear scalability. Caching allows processing and resources to be reused,
alleviating the need to reprocess pages or reallocate resources. Disregarding other
influences, efficient caching can result in superior linear application server scalability.
Resource management becomes more complicated as the quantity of resources
increases. The extra overhead for resource management, including resource reuse
mechanisms, reduces the ability of application servers to scale linearly relative to
constraining resources. For example, when an extra processor is added to a single
processor server, the operating system incurs extra overhead in synchronizing threads
and resources across processors to provide Symmetric Multi-Processing. Part of the
additional processing power that the second processor provides is used by the
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