- The Emergence of Web Applications
- Basic Definitions
- The Nature of the Web and Its Challenges
- Performance and Scalability
- The Internet Medium
- Wide Audience
- Always On
- Lack of Complete Control
- Measuring Performance and Scalability
- Measuring Performance
- Beyond Benchmarking
- Measuring Scalability
- Throughput and Price/Performance
- Scalability and Performance Hints
- Think End-to-End
- Scalability Doesn't Equal Performance
On the Internet, consumers query providers for information. Unlike in other media, information is not distributed at the whim of the provider. Instead, consumers request information via queries, which consist of a series of interactions between the client and server.
In addition to querying, consumer requests can contain submitted information that must be processed. This submission mechanism can be explicit or implicit. Explicit submission is the user's deliberate transmission of information to the provider, such as a completed HTML form. In contrast, implicit submission is the provision of data through the user's Web session. Cookies are a good example of this, in that they consist of data that is chosen by either the provider (e.g., for page tracking) or the consumer (e.g., for personalization).
Regardless of how the information is submitted, the application's processing must often be based on this information. Thus, the Internet is not simply a library where clients request items that exist on shelves; rather, requests involve calculations or processing, sometimes leading to a unique result. Furthermore, the interactive nature of the Web means that a request cannot be fulfilled in advanceinstead, the application must respond at the time the request is made, even though substantial processing may be associated with that request.