01111nas a2200157   4500000000100000000000100001008004100002260003600043100001900079700002400098700002200122700002400144245007000168300001400238520070100252       2010                            d  bIITiS PANaGliwice, Bałtycka 51 aAdam Józefiok1 aTadeusz Czachórski1 aKrzysztof Grochla1 aTadeusz Czachórski00aPerformance evaluation of multiuser interactive networking system  a223–2313 aThe article presents a work in progress aiming at performance evaluation of a large database system at an assurance company. The system includes a server with a database and a local area network with a number of terminals where the company employees run applications that introduce documents or retrieve them from the database. We discuss a model of clients activities. Measurements were collected inside the working system: the phases at each users application were identified and their duration was measured. The collected data are used to construct a synthetic model of applications activities which is then applied to predict the system bahaviour in case of the growth of the number of users.