Storage Performance and Capacity Planning

Revolution – the first 2000 years of computing is the Computer History Museum‘s latest exhibit.  And what a show!  You can see models of early computational machines, short videos explaining how things work, and room after room of computer artifacts.  Storage technology has its own place in the tubes, transistors, delay lines, rotating disks and drums, bubbles, and other exotic media.

Beyond storage, the exhibit chronicles software, hardware, games, primary uses for computers throughout the ages, and much more.  You’ll be amazed at how well the show is put together. If you’re at all fascinated by computers, this is a must see!

Have you ever wondered how the performance of your storage subsystem compares to that of others? You may know how many IOs per second your subsystem does, or how many megabytes per second of data it delivers, but how does that compare to other subsystems in other IT shops?

The IO Rate and Response Time scatter plot shows IO rates from about 2,000 IO/sec to 200,000 IO/sec, and response times ranging from a fraction of a millisecond to about 15 msec of response time. Where might your subsystem fall in this space? Let’s look at datarates next.

This scatter plot shows datarates from less than 100 MB/sec to well over 2000 MB/sec, and response times from a fraction of a millisecond to about 60 msec per IO. There is a trend in this data that correlates higher datarates with higher response times.

Thinking about the performance of traditional disk storage, things have really changed, and rather suddenly.

• Storage capacity of disks has exploded.
• Solid State Devices are finally making real inroads
• To make it all simple – virtualization of everything from servers, to storage, and the networks in between!

Computer disk storage has recently crossed into a new pricing realm. Storage capacity has become inexpensive to the point that access to storage (performance) becomes the major cost consideration.