TECHNIQUES FOR UPDATE HANDLING IN THE ENHANCED CLIENT-SERVER DBMS

The Client-Server computing paradigm has significantly influenced the way modern Database Management Systems are designed and built. In such systems, clients maintain data pages in their main-memory caches, ori ginating from the server's database. The Enhanced Client-Server archit ecture takes advantage of all the available client resources, includin g their long-term memory. Clients can cache server data into their own disk units if these data are part of their operational spaces. Howeve r, when updates occur at the server, a number of clients may need to n ot only be notified about these changes, but also obtain portions of t he updates as well. In this paper, we examine the problem of managing server imposed updates that affect data cached on client disk managers . We propose a number of server update propagation techniques in the c ontext of the Enhanced Client-Server DBMS architecture, and examine th e performance of these strategies through detailed simulation experime nts. In addition, we study how the various settings of the network aff ect the performance of these policies.