Performance Isn’t What It Used to Be - The Data Access - page 4

Before Database Connectivity Standards

Application Application

API 1 API 2 API 3 API 1 API 2 API 3

After Database Connectivity Standards

Application

Standard API

Figure 1-3 Emergence of database connectivity standards

Where Are We Today?

Today, even when the database is tuned well, we know that database applications
don't always perform as well as we would like. Where does that leave us? Where
do we find the performance issues today? For the majority of database applica-
tions, the performance issues are now found in the database middleware. For
most applications, 75% to 95% of the time it takes to process a data request is
spent in the database middleware compared to 10 to 15 years ago, when the
majority of the time was spent in the database management software.
In most cases, performance issues seen in database applications are caused
by the following:

• The network

• Database drivers