Expert knowledge for digital decisions
What Does 'Scalable' Mean in Software?
Short answer
Three Types of Growth
More simultaneous users. Ten or a thousand people at the same time makes a significant difference in architecture.
More data. A search over ten thousand records is trivial, but over ten million is no longer so.
More processes. One hundred orders a day or one hundred thousand requires different processing.
These three rarely grow evenly – and you should know which one increases first for you.
What Scalability Means in Practice
- Clean database structure with appropriate indexes
- Intensive work in the background, not while the user waits
- Cache for frequently read data
- The ability to add a second server alongside
The Costly Mistake in Both Directions
Too little: After two years, the system is slow, and the repair costs more than the original setup.
Too much: An architecture for millions of users with only twenty actual users. More expensive to build and operate, and no one understands it anymore.
The Right Question
Not "is it scalable?", but "for what quantity are we building in five years?" Providing an honest answer to this is more valuable than any technical commitment.
Key facts
- Three Dimensions
- Users, Data Volume, Processes
- Right Question
- For what quantity are we building in five years?