Database Reference
In-Depth Information
important. Understanding what your SQL Server needs for resources and sizing the
virtual machine that houses it accordingly will avoid a lot of problems. The opposite is
also true: Oversizing or over-allocating your VMs will introduce a lot inefficiencies
and potential problems into your shared environment.
Is Your Database Too Big to Virtualize?
A common objection I hear from DBAs when they are first asked to consider
virtualizing a database is that their database is too big and complex to be virtualized.
Consider this example of a very large and complex database that was virtualized. It had
the following characteristics:
8TB in size
8.8 billion rows of data
52 million transactions per day
79,000 IOPS
40,000 named users
4,000 peak concurrent users
Complex ERP system
After this database was virtualized, all transaction types got better. According to the
DBA, they saw more than a 50% reduction in time for online transactions. When done
correctly, it's possible to virtualize very large and complex databases.
Summary
In this chapter, we discussed the business case for virtualization, including ROI.
Companies operating in a one-server-to-one-application environment has led to a
number of costly inefficiencies in how businesses operate. Companies that adopt
virtualization typically see significant cost savings and increased utilization.
This has created a very powerful financial reason to adopt virtualization. Combined
with the many capabilities of a virtualized infrastructure, this provides a DBA with
many options. The inherent capabilities surrounding redundancy up and down the entire
infrastructure stack that comes with a virtualized platform will improve the availability
of the databases, enabling you to exceed the documented and undocumented service
levels you have with your customers.
We also discussed how virtualization has created an abstracted layer from the physical
environment; once you break your databases away from the shackles of the physical
server hardware, hardware becomes a commodity you can easily leverage. We stressed
the importance of understanding the resource requirements of your database in a shared
environment, and how important it is to size the VM that houses the database
