Database Reference
In-Depth Information
It's About Me, No One Else But Me
From your perspective as a DBA, when you set up a database in the physical world, it's
typically about “me,” just “me,” and no one else but “me.” It's your database server,
and everyone else on it is either an invited guest or an unwanted visitor. As we have
been discussing, this is the world of a one-to-one relationship. Your production
database sits on a server whose only purpose is to support the production SQL Server
database that supports the business. When it sits idle, those resources go to waste. If you
need more resources, you are limited to what the physical server the database sits on
was purchased with.
As a DBA, you tune up the database to take full advantage of all resources available to
it. For example, Max Server Memory would be configured to take advantage of the
entire RAM on the box, except what is needed for the operating systems. You are only
setting a small amount of RAM aside because it is good for me. Max Server Memory is
talked about in great detail in
Chapter 7
, “
Architecting for Performance: Memory
.
” In
fact, when databases get moved onto storage arrays, as DBAs, we don't take too well to
that at first. This means it's not just about “me.” You have to deal with a storage array
administrator who may not have the best interests of the database as their top priority.
The storage administrator needs to ensure performance for all the systems connected to
the array, not just the database servers.
Let's face it: As DBAs, we don't play well in the sandbox with others. We have grown
up in a world where we don't have to share and we are not historically good about it.
We have grown up in a world where we have to solve problems by ourselves all the
time. When you virtualize your database, it's important to note that the world changes.
There are others in the sandbox with you. You have to learn how to share and rely on
others if you are to succeed. Good communication and understanding of your
requirements among the different teams is critical in this new world.
Virtualized Database: It's About Us, All of Us
In the case of a virtualized environment, it is a shared environment. This means you
have to consider that others need access to the CPU, memory, and disk resources, which
is why we talked about virtualization being a one-to-many relationship, where the
“many” represent the different hosts running a single physical host/server.
As DBAs, this means we need to behave a little differently if we want to be successful
when we virtualize the database. As DBAs, we understand that everything has tradeoffs.
When we give the database more CPU, it typically minimizes I/O. In fact, as database
administrators we are constantly being asked to look at the infrastructure and make
decisions on how the database and programs running on the database consume resources
to help the overall throughput within the database improve. We now need to make those
tradeoffs within the overall shared environment. If we behave a little differently with
