An Architecture for a WWW Workload Generator

1 Overview SURGE (Scalable URL Reference Generator) is a WWW workload generator which is based on analytical models of WWW use. It relies on the fact that a great deal of prior work has been done in the analysis of WWW transactions, and that models for many of the important characteristics of WWW use have been developed. The goal of SURGE is to provide a scalable framework which, from the server's perspective, makes document requests which mimic a set of real users. SURGE is intended to be used for benchmarking, network traac generation and simulation. This paper contains descriptions of the details of the SURGE framework, the additional models which we developed, and the statistical methods we used to parameterize the models. 2 The SURGE Framework 2.1 Structure of SURGE SURGE is a scalable software framework within which a collection of models for the various components of WWW use are combined. From the top down, SURGE software resides on a set of clients which are connected to a WWW server as illustrated in Figure 1. Each SURGE client executes a set of threads, each of which is an ON/OFF source 15, 9]. Each thread requests a document set which is then transfered by the server (ON time). After receiving the document set, a thread sleeps for some amount of time (OFF time). This ON/OFF characteristic is an important diierence between SURGE and other benchmarks such as 1, 2, 3, 4, 5] (14] also includes OFF times).