Databases Reference
In-Depth Information
Our goal is to identify these bottlenecks and hopefully mitigate them during the pre deployment stages.
We talk about various aspects of the application life cycle starting from sizing your architecture to parti-
tioning large tables without delving into the actual details, as they have been covered elsewhere in this
book. However, as luck would have it, even though a lot can be done during the pre-deployment stages,
every DBA faces issues post production. The latter part of the chapter talks about certain limitations faced
when tuning production systems.
Best Practice
Find the bottlenecks before your production deployment.
Sizing
One of the most important steps in the database deployment life cycle is sizing. In order to accurately size
a production environment it is important to take into consideration a variety of factors such as database
size, number of transactions, number of users, and so on. Incorrectly sized production architecture often
becomes the main reason for poor performance.
The SQL Server database world has become increasingly complex over the years. Today, multi-terabyte
databases run alongside small to medium-size implementations. The variability in deployments is enor-
mous and this leads to numerous hardware combinations possible. Thus, every deployment is different
and there is no one-size-fits-all policy. Nevertheless, there are some common guidelines followed by most
companies around the world when it comes to sizing their database architecture.
The process begins with the choice of a hardware vendor which for medium to large companies sel-
dom differs from project to project. The next step involves answering a series of questions to deter-
mine the specific hardware requirements for the deployment. This process differs from application to
application and is based on the criticality of the applications. However, below are some more com-
mon questions that every DBA needs to answer when correctly sizing a SQL Server database
deployment:
What editions of SQL Server will be deployed?
❑
Howmany SQL Server instances will be deployed?
❑
How many databases per instance?
❑
How many users per database?
❑
❑
Average size of a database?
❑
Average estimated size of tempdb?
❑
High availability requirements?
These questions are meant to provide the DBA with valuable insight into the SQL Server deployment.
Answering some of the questions may require the help of the development team or business analyst
team. This process is generally easier for packaged applications such as Siebel, PeopleSoft, or SAP, as the
application vendor typically provides a list of recommended hardware configurations for the database
backend. A sizing review may also be provided by these vendors as a paid option. If your application is
Search WWH ::
Custom Search