After years of working with SaaS customers, I hear every day about horror stories and challenges related to scaling. Simply put: scaling can be a headache. SaaS applications thrive - or die - on the performance of their infrastructure and as you grow you'll have no choice but to face the scaling dilemma. How you scale your application to distribute traffic and run your code can mean the difference between an instant response for users or users waiting for your app to respond or update.
Since scaling your app is a key concern regardless of whether you’re a start-up or “grown-up” SaaS app, I want to make sure you understand the differences and how they impact your growth strategy:
Imagine a car that can only fit four people, but you have a family of eight. You can buy more four-person cars and link them together in an extended caravan or you can buy a bigger vehicle to accommodate everyone.
Horizontal scaling is akin to the caravan rolling down the highway. Horizontally scaling addresses capacity needs by adding more resources to the existing architecture. You can add as many cars as you need to accommodate the family as it grows.
Vertical scaling is buying the bigger car. A vertically scaled architecture adds resources: more memory, more storage, faster processors, etc. to the existing architecture. It’s like expanding the current vehicle from a four- to an eight-seater without having to re-adjust the mirrors.
Do you really need to take all eight family members out every time you leave the house? Is there a gas savings between the two methods? What is the cost comparison? These are the same types of questions SaaS businesses face in deciding whether to build their app to scale by replicating identical servers with horizontal architecture or to grow the servers in place with vertical scaling or a combination of both. The top reasons customers bring their apps to Rackspace for SaaS application hosting revolve around looking for ways to plan for efficient scale or trying to harness a SaaS application that has already become a scaling headache.
Be sure to check out Kevin’s next video where he discusses the importance of being consistent in your SaaS environment. Learn more about hosting SaaS applications at Rackspace.