------------------------------------------------------------------------------- B O S T O N U N I V E R S I T Y Computer Science Department C O L L O Q U I U M Monday April 4, 1994 11:00am (Coffee served at 10:30am) Seminar Room / MCS 135 ------------------------------------------------------------------------------- FETCHING AND PREFETCHING IN A DISTRIBUTED OBJECT-ORIENTED DATABASE Mark Day Massachusetts Institute of Technology In the Thor distributed object-oriented database, objects are stored at servers and fetched to client machines on demand. The mechanism to implement this "object faulting" is typically implemented by either marking objects (so-called "node marking") or by marking pointers ("edge marking"). I will discuss the design issues involved in the object fault mechanism, and present data from the Thor implementation for both techniques with different levels of speculative prefetching. Node marking is superior for workloads that repeatedly use objects already at the client. Edge marking is superior for workloads that fetch a lot of objects from the server, especially if relatively few of those are actually used. Host: Prof. Steve Homer ------------------------------------------------------------------------------- For more information contact Prof. Azer Bestavros -------------------------------------------------------------------------------