Scaling a web application is considered one of the final phases of developing a web app. But in most cases, this strategy is the wrong one. What should you do when your number of visitors quickly increases? If enough preparations are not made on time, the application's performance will degrade, and you will lose potential consumers. In addition, the cost and effort to scale applications will also reduce.

In this article, we’ll discuss the complete concept of app scaling and provide the most effective tips to build the best scaling web applications.

What is app scaling when it comes to web applications?

Web application scalability refers to an application's capacity to expand over time (i.e., how the app handles the increasing number of users). An application is considered scalable if it continues to function normally, whether there are hundreds or thousands of users. Therefore, scaling app is one of the most significant concerns in providing a satisfying experience for the user.

For scaling web applications, you need an acceptable strategy for the system's architecture and the program's development, one that considers all the app's components. It is also important to select the appropriate cloud solutions and be aware of how to set them up to meet your requirements effectively. It is not a simple adjustment that can be made in a matter of minutes; instead, it is a lengthy process. That’s why it’s never odd to emphasize the importance of in-advance scaling of any web app. 

But before we dive into the very tips, let’s take a quick look at the types and the importance of scaling applications.  

Horizontal scaling vs. Vertical scaling

Let's start with the fundamentals by discussing the two physical scaling methods. The chances are that concepts of horizontal and vertical scaling are new to you, so we decided to demonstrate them first.

Horizontal scaling

What people usually mean when they refer to "horizontal scaling" is that they intend to increase the number of their current web servers by at least one to handle a larger number of users (or their requests). Such an approach definitely provides you with the benefit of more elasticity. 

Due to the ease with which several servers may be set up in a short period, they offer to boot up and tear down as needed. This method is often employed in cloud computing settings (let it be AWS Auto Scaling Group or any other similar tool). 

However, the trade-off for this limitless scalability is that your app must remain stateless for the most part. Additionally, it’s hard to maintain consistency across multiple servers, while the process also requires cross-domain communication.

Vertical scaling

Vertical scaling is the inverse of horizontal scaling (as the name suggests) and refers to "raising" web server resources so they can handle more traffic. This method shines when used to stateful apps that will never see more than a fixed volume of user requests. 

Having low maintenance costs and better data consistency, this methodology is most frequently seen in a central database. Most database engines have few options for scalability, forcing you to increase the resources of current instances to ensure that database queries complete promptly or achieve increased throughput.

The main cons of vertical scaling thought would be higher chances of downtime due to server changes and more manual efforts for implementation. 

Why is scalability important?

Nowadays, users want a web application that can load instantly, is always on, and works well even when many individuals use it simultaneously. As a result, people will stop using your app in favor of one that can actually scale with its user base and, thus, provides a better user experience.

Scalability is a crucial component of software for the following reasons:

  • It affects an organization's capability to meet the ever-changing demands of the network infrastructure.
  • If the company's expansion surpasses the capabilities of its network, it may lead to service disruptions, which in turn may cause customers to leave. Therefore, it is essential to take the necessary steps to guarantee that you have high availability at all times because doing so will assist you in retaining pleased consumers.
  • During the off-season, when there is less demand for your goods or services, you may be able to reduce the size of your network infrastructure and save money as a result.

Generally, businesses place a greater emphasis on product features and less on their ability to scale. Forgetting about scalability is often a mistake, it’s necessary for the existence of any online application; otherwise, it will simply fail to perform as expected. 

If you prioritize it from the beginning, you will have cheaper maintenance costs, a better user experience, and increased agility.

6 tips on how to do web app scaling right

Now that you understand application scalability, its types, and importance, let's look at some tips you need to keep in mind while developing scalable web apps:

  1. Assess the requirement for scaling and expectation management

Don't waste time and effort trying to increase scalability if you don't have to. It may be expensive to scale a web application in your case. Ensure the costs will be covered by your anticipated growth (and not because everyone is talking about scalability).

Consider the following steps before making a choice:

  • First, collect data to ensure that your web application aligns with your expansion goal. (Have you seen a rise in the number of people using this service? How much will it change, and over what period? What are some things you hope to do in the coming days/weeks/months?)
  • Answer the question: ‘What storage strategy are you utilizing, and how adaptable is it to varying amounts of space?’
  • Define the options open to you when you significantly increase the number of users and data traffic.
  1. Define your scalability issue with the use of metrics

Let's pretend that you've reached a point where you need to increase the capacity of your web app. You'll have to choose which concerns about scalability should get your attention in the first place. 

The following four measures of scalability can help you do this:

  • Memory usage measures how much random access memory (RAM) a specific system uses within a given time interval.
  • High Central Processing Unit (CPU) utilization usually means your software is having performance troubles. For most app-tracking software, this is a must-have indicator to track.
  • Network Input/Output is the amount of time it takes for one tracked process to transfer data to another. Identify how many time-consuming processes you currently have (or will have in the future).
  • Input/Output Disk operations are any actions performed on a physical disk. Don’t forget to calculate these, as well. 

The higher these indicators are, the more likely your web app requires to be scaled. You can find more info on calculating those in this article. 

  1. Pick out a set of tools to keep an eye on application scalability

Now that you know which metrics are most important, you may get app-monitoring solutions to keep tabs on them. The process is simplified by the availability of high-quality application performance management (APM) tools from industry leaders in PaaS (like Heroku) and IaaS (like AWS). 

For instance, Heroku employs a New Relic add-on, and Amazon Web Services' Elastic Beanstalk offers its built-in monitoring system. 

  1. Use the right scalability-enhancing infrastructure solutions

Let's say you're a brand new company making a web app. Using a PaaS (like Heroku) or an IaaS (like AWS) is advised because these Cloud services free up your hands from many of the responsibilities associated with building and maintaining a web application. 

Infrastructure and storage, servers, networking, databases, middleware, and the runtime environment all fall under this category. Auto-scaling, consistent availability, and service level agreements (SLAs) are just a few of the features of PaaS and IaaS that can facilitate scaling.

  1. Select the optimal software architectural pattern

Web applications with a scalable architecture can swiftly respond to changing user needs and deliver optimal performance at the same time. As a result, scalability problems can have a profound effect on architecture. For scalability, two primary architecture patterns are considered: both the Monolithic and Microservices Architecture styles are in use today. Monolithic architecture is the best match for eCommerce or SaaS applications, while Microservices is a better practice for large apps which have all their elements working separately and independently from one another (e.g., Netflix, Spotify, PayPal). 

  1. Selecting the ideal database to scale

After addressing the infrastructure and architecture, the database becomes a significant emphasis when discussing scaling. Whether you choose a relational database (like MySQL or PostgreSQL) or an unstructured one (like Google Drive) depends on the data you need to keep (NoSQL database, like MongoDB).

Final Verdict

You need to remember that if your app does not have an appropriate scaling mechanism, it will most likely not make it to the following day if there is a sudden and significant increase in the number of users. 

You have to be adaptable and quick to respond to different situations as they arise. As you have seen, there are plenty of factors and obstacles to consider when scaling web applications. That's why scalability is necessary if you want your startup to be successful and to produce a successful product that satisfies the expanding expectations of the market. 

Remember that you don’t have to be alone when scaling your web application. Apptension is qualified and prepared to assist you with scaling, and even more product maintenance tasks, including bug fixes, feature extensions, and tech/UX audits.

We created a handful of mobile apps and scaled them accordingly to our client’s needs, so why not speak to one of our experts? We will provide an application tailored precisely to the needs of your company. Want more information? Just contact us!