SQL Server Tips by Robin Schumacher

The Impact of Availability

How does availability impact the performance model? The best way to grasp this concept is to delve into several different availability-related situations and examine their impact on the performance model.

Of course, the first situation to consider is what happens when the database server suddenly goes down. The impact of this situation is fairly easy to assess. When the availability suddenly drops to zero, the peak efficiency of the database would be at zero as well.

While database server accessibility components have the potential to cause a sudden, catastrophic drop in the peak efficiency model, other components can crash a system just as easily, but the end of the story will not be quite as abrupt. One case to consider could involve lock contention, one of the building blocks of resource availability.

The above book excerpt is from:

High-Performance SQL Server DBA
Tuning & Optimization Secrets

ISBN: 0-9761573-6-5
Robin Schumacher

 http://www.rampant-books.com/book_2005_2_sql_server_dba.htm