Just added…
"A service is said to be scalable if when we increase the resources in a system, it results in increased performance in a manner proportional to resources added.
An always-on service is said to be scalable if adding resources to facilitate redundancy does not result in a loss of performance."
– Werner Vogels, CTO – Amazon.com
Here is Werner’s full post:
http://www.allthingsdistributed.com/2006/03/a_word_on_scalability.html
