Scale-Up and Scale-Out question

Question

anyone knows the difference between Scale-Up and Scale-Out in application design and development

Alan · Answer

Here are some good general definitions of these terms which I found in Wikipedia: To scale vertically (or scale up ) means to add resources to a single node in a system typically involving the addition of CPUs or memory to a single computer. This could also mean expanding the number of running processes such as increasing the number of Apache daemons. To scale horizontally (or scale out ) means to add more nodes to a system such as adding a new computer to a distributed software application. An example might be scaling out from 1 web server to 3.