Database Wait Time

The amount of time the user spends waiting for the system to respond or for an operation to complete is called the database wait time. Poor system response time prevents users from performing their tasks efficiently. Thus, one of the primary jobs of the database administrator (DBA) is to reduce the database wait time as much as possible.

Before the DBA can attempt to reduce the length of time spent waiting for the database to perform, he or she must first identify what functions are causing the system to stall. To accomplish this, a thorough analysis of the system's performance over a specified period of time is required. Once this information is obtained, the DBA can then use it to identify performance trends.

Finally, the DBA can take the wait time information gathered and extrapolate it to graphical or tabular reports that clearly identify when and where the bottlenecks occur. Having the database wait time information on hand helps the DBA to better plan for heavy workloads periods. Furthermore, this information can also be used to justify the need for system upgrades to upper management.

Gathering the Information

To assist the DBA with the task of monitoring and subsequently identifying the top database wait times, the DBA could spend time writing customized scripts to gather key information from the database. As an alternative, the DBA might consider investing in a pre-configured database performance monitoring software product. The majority of these products come preloaded with the tools necessary for gathering and analyzing typical database wait time statistics.