Database Reference
In-Depth Information
network administrators to work with you to meet your requirements.
This means working closing with the storage administrator, network administrators, and
vSphere administrators. As our coauthor Michael Corey likes to say, “I flunked Mind
Reading. If you don't tell me what you need, I won't know.”
Shared Environment Means Access to More If You Need It
By embracing this new way of thinking, you can start to harvest the advantages of
virtualization. As the DBA, let's say you know that there is special processing that
happens every year that is critical to the business. This year-end processing has
historically brought database performance to a slow crawl. In this shared environment,
you now have more resources to work with. You as part of a team have choices you can
make. You could give the virtual machine that houses the database access to more
resources; you could also take resources away from other VMs, freeing them up for the
database. What is important to realize is that a virtualized database can be given
resources quickly and easily. In fact, you could also just move the database while it's
being used onto another physical host that has more resources available. No longer do
you have to hoard or squirrel away resources.
Check It Before You Wreck It
I want to talk about the “check it before you wreck it” rule. As a DBA, you embrace this
new way of doing business. You determine how many IOPS the new database you are
about to build needs. In this new world of shared responsibilities, we would encourage
you to work with the storage administrator to determine together the IOPS requirements
of the database. The more you start approaching the support of the infrastructure as a
team, the better off you will be down the road.
For the purposes of this example, it is assumed you determined the IOPS requirements
for the database and then communicated all the requirements to the team. You are
handed back a virtual machine to put the new database on. Before you go install the
database, do a simple IOPS test. Make sure the VM was configured with what you
asked for. You can use simple tools such as SQLIO and IOMETER to check it. Before
you go and install the database, as Jeff would say, “Check it before you wreck it.”
If it's not as you specified, revisit the request with the team so that it can be
reconfigured. Use this as a learning experience and stress with the team the importance
of providing you a VM capable of meeting the demands the database requires.
The database is too resource intensive a VM not to be configured appropriately.
Experience has taught us that early on, many virtual environments were built for
capacity, not performance. That the vSphere administrators have been able to
overcommits a lot of resources like CPU and memory in the vSphere environment and
