Workload Synthesis of the simulation model

Types of events recored during simulation :

page read, page write, disk read, disk write, file open, and file close

Factors that affect throughput in a multiuser environment :

• the number of concurrent queries,
• the degree of data sharing, and
• the query mix

Levels of data sharing defined :

• full sharing, all queries access the same database;
• half sharing, every two queries share a copy of the database; and
• no sharing, every query has its own copy.

Query mix selection is based on the consumption of three system resources :

• CPU cycles,
• Disk bandwidth, and
• Amount of main memory utilized by the query

Following table shows the Query classification :

Query CPU Disk Memory

Type Demand Demand Demand

I Low Low Low

II Low High Low

III High Low Low

IV High High Low

V High Low High

VI High High High