How to: Create Scalable Software

Software development requires a long-term mindset. Your software should still be functional, efficient, and relevant years after you initially implement it. It’s unrealistic to expect your business to remain exactly the same years from now—so why should your software be any different? Scalability is the factor that accounts for the need to evolve your software along with your business. 

What Is Software Scalability?

Software scalability describes a system’s ability to continue to function optimally even as user demand increases. As your business continues to grow and its needs evolve, the software you use will need to be updated in order to keep up. Scalable software makes the process of scaling your business much smoother because it can be easily updated or altered without creating unnecessary friction.

Vertical scaling vs. horizontal scaling

There are two overarching methods of scaling software: vertical scaling, or scaling up, and horizontal scaling, or scaling out.

Vertical scaling

accounts for increasing user demand by adding on to existing hardware. While upgrading the hardware can improve scalability, using just one machine means the scaling process will require a lot of downtime.

Horizontal scaling

adds more machine instances instead of upgrading a single machine. This distributes the load across multiple pieces of hardware and makes it possible to make alterations for scalability without downtime.

Why Is Software Scalability Important?

At the most basic level, the advantage of scalable software is that it enables you to take on additional user demand without affecting the system’s performance. But this is just the tip of the iceberg; the ability to safely increase user demand comes with several other benefits, as well.

Long-term adaptability Scalability doesn’t only mean the software can hold steady as demand from users grows—truly scalable software can support the addition of new features as business needs expand. When software isn’t scalable, its performance decreases as its workload increases. Scalable software is exactly the opposite: Its functionality can be continually improved even as you increase its workload.

This means you don’t have to try to include every feature you might ever need on day one. If the software is scalable, you can start small and scale gradually. You shouldn’t use scalability as an excuse to adopt a “fix-it-later” attitude and rush out an incomplete final product, but you can use it to plan for future growth instead of overcommitting resources now.

Short-term adaptability Even if you make a plan to scale your software over time, sometimes unexpected factors arise. Software development is rarely a linear process, and when it’s necessary to pivot, you’ll be left high and dry if your software isn’t scalable. Scalability will also be a huge asset to your efforts to gain an edge over the competition. The more flexible your software is, the easier it will be to keep it relevant as your market landscape inevitably shifts.

Resource reduction Scalability might not seem like a very high priority at first. You’ve built it to handle the current workload, and it functions smoothly. However, it's very easy to underestimate future needs. If you don’t take scalability into account well before it’s necessary, you’ll find yourself without any good options when the software reaches its limit. Factoring in scalability during development ensures you avoid a tedious and expensive upgrade or replacement process in the future.

How Do You Create Scalable Software?

Here are a few ways to improve your software’s scalability:

Plan for future functionality

During the development process, you should take growth and future needs into account. But it’s not enough just to be aware that scaling will be necessary—you need to make a plan for the kind of features you anticipate adding and the pace at which you want to scale. You don’t need to map out every detail because the software’s lifecycle is unlikely to unfold exactly as anticipated, but having a target to aim for can help you design a scalable framework with relevant updates in mind.

Write clean code

It’s easy to overlook the quality of the software’s code as a scalability factor, but when code is well-written it can make it much easier to alter the software down the line. If it wasn’t written to be scalable in the first place, there may be no way to scale the software without substantially changing the original code. Keeping the coding clean and simple can also make life easier for other programmers that may be working on the software in the future.

Improve memory management

Investing in memory management optimization can improve software scalability. Data levels can easily fluctuate along with changing user demand. If large amounts of users are connecting to the software at once, data levels may rise without warning, and your software’s data capacity will need to be able to scale to accommodate this.

Don’t use local storage

Files should be stored remotely, not locally, for maximum scalability. This way, files can be saved without using up any local resources, and they can be retrieved in a scalable manner using a CDN. Static content, especially, should be served using a CDN, whereas your web server is better suited for serving dynamic content.

Use stateless applications

Stateful applications perform transactions as part of a periodic, ongoing exchange of requests and responses. Each request and response are made within the context of the ongoing process, affected by the preceding transactions. The data to provide this context must be retrieved from the same server every time.

A stateless application, on the other hand, works in isolation. It does not maintain an ongoing exchange; each transaction is completely unaffected by other transactions that have been performed. This means the server does not need to store any information by which to reference those past transactions. Stateless applications are more scalable than stateful applications because they don’t require any additional storage space to be allocated as user demand increases.

Use asynchronous processing

Employing asynchronous processing to handle non-critical tasks allows you to complete those tasks without eating up more resources than necessary. Lower priority tasks can run asynchronously in the background so that more resources can be directed toward supporting increased user demand. If you can optimize resource allocation, your system will have a higher capacity to support a sudden increase in user demand.

How Do You Know When Your Software Is Scalable?

Software scalability is not something that’s achieved once and checked off a list. It’s an ongoing process that requires periodic reassessment as your business needs continue to grow. You should test scalability when you’re planning to add features or make other major updates to ensure the change won’t hurt performance, but you should keep scalability on your radar even if you aren’t planning to scale your software’s features soon. Every system has a maximum workload it can handle, and it’s better to know where it is before you reach it. This will allow you to increase capacity proactively instead of reactively. To measure your software’s scalability, try evaluating these metrics:

Throughput

A system’s throughput is the number of requests the software is processing over a given period of time. If the system’s throughput remains consistent across differing workloads, the software is considered scalable in that regard.

Response time

Response time is the amount of time it takes the software to respond to a user request. Scalable software can maintain the same response time regardless of the level of user demand. By measuring the system’s response time while gradually increasing its workload, you can pinpoint the demand threshold over which the software would cease to function at all.

Memory usage

Memory usage is simply the amount of memory that must be allocated for the software to function optimally. If memory usage is too high, the software won’t scale efficiently. Keeping memory usage low by following best practices during the programming stage can improve scalability.

CPU usage

CPU usage is the number of megaHertz of central processing unit power that the software is tying up. The less CPU usage required for the software to perform optimally, the more scalable the software.

Nearshore Software Development 

Creating and maintaining scalable software requires a great developer. It’s no easy task to design a system that will continue to support a business’s needs for years to come.

If you want to make sure your software is ready to scale alongside your business, KNDCODE has got you covered. We can help you improve your software’s scalability so you don’t have to wonder when it’s going to reach its limit. Our nearshore software development services are provided by an experienced team of developers based in Indiana and Central America (Guatemala and El Salvador) . Nearshore software development services can deliver quality results at an attractive price point.

KNDCODE. Always ahead, forward, near.