The primary difference between horizontal scaling and vertical scaling is that horizontal scaling involves adding more machines or nodes to a system, while vertical scaling involves adding more power (CPU, RAM, storage, etc.) to an existing machine. In other words, horizontal scaling involves scaling out, while vertical scaling involves scaling up. Horizontal scaling is typically used to handle increasing amounts of traffic or workload, while vertical scaling is typically used to handle resource-intensive tasks or applications that require more processing power.
As we expand our operations or our clientele base develops, hundreds of things change. From employee strength to resource count, we scale upwards. Similarly, when the business is growing, our cloud infrastructure also alters. As a result, we need enhanced cloud computing power to serve the new customers and maintain the new databases. But, given scalability options, i.e., horizontal and vertical scaling, it may take time to choose what is right for your business and what advantages/disadvantages it will offer. So, let’s explore the horizontal vs vertical scaling AWS offerings and explore the same.
What is horizontal scaling?
Horizontal scaling, often known as “scaling out,” is the process of increasing the number of nodes and machines in the resource pool. For a sequential piece of logic to be processed in parallel across numerous devices, horizontal scaling calls for breaking it into smaller chunks and delegating the logic to the new machine. In simpler terms, scaling horizontally is about hiring new employees for an additional client/problem set.
Pros:
- Easier Scaling from Hardware additions
- Enhanced Flexibility
- Lesser Downtime
- Offers Redundancy
Cons:
- Higher initial costs involved
- Harder to maintain
What is vertical scaling?
Vertical scaling, often known as “scaling up,” is the process of increasing the power of an existing system, such as the CPU or RAM, to meet the rising demands. Because there is no need to alter the logic, vertical scaling is simpler. Instead, you are only executing the same code on machines with more capacity.
The memory, storage, or network speed can be vertically scaled. Vertical scaling can also refer to completely replacing a server or shifting the workload from an outdated server to an updated one. In simpler terms, Vertical scaling is about upskilling existing employees for an additional client/problem set.
Pros:
- Cost Effective
- Less Complexity involved
- Easier to maintain
Cons:
- More Downtime possibilities
- Very less flexibility
- Single Point of Failure
Horizontal vs vertical scaling:
The following differences will help you delve into the deep understanding of horizontal vs vertical scaling:
| Fundamentals | Horizontal Scaling | Vertical Scaling |
| Data Management | Scaling horizontally typically relies on data partitioning as each node only contains part of the data. | In vertical scaling, the data resides on a single node, and scaling is accomplished by multi-core, primarily by distributing the load among the machine’s CPU and RAM resources. |
| Examples | Cassandra, MongoDB, Google Cloud Spanner | MySQL and Amazon RDS |
| Downtime possibility | You can scale with less downtime by adding additional computers to the existing pool because you are no longer constrained by the capacity of a single device. | There is an upper physical limit to vertical scaling, which is the scale of the current hardware.Vertical scaling is restricted to the capacity of one machine because expanding over that limit can result in downtime. |
| Concurrency Models | As it entails distributing jobs among devices over a network is known as distributed programming. Several patterns are connected to this model: MapReduce, Master/Worker*, Blackboard, and many spaces. | It involves the Actor model: Multi-threading and in-process message forwarding are frequently used to implement concurrent programming on multi-core platforms. |
| Message Passing | Data sharing is more difficult in distributed computing because there isn’t a shared address space. Since you will send copies of the data, it also increases the cost of sharing, transferring, or updating data. | Data sharing and message passing Can be accomplished by passing a reference in a multi-threaded scenario since it is reasonable to presume that there is a shared address space. |
Horizontal vs vertical scaling: Which one to choose?
Numerous factors help you determine which type of scaling will suit your business objectives the best! So, here are the determinants helping you choose the most appropriate out of Horizontal scaling vs. Vertical Scaling-
- Performance: By scaling out, you can pool the computing capacity of several physical machines by combining and leveraging the computing power of all nodes. You are thus not constrained by the capability of a single unit. But if you have enough resources on a single system to meet your scalability requirements, vertical scaling can be an appropriate fit.
- Cost: Horizontal upgrades have higher up-front hardware expenditures. Vertical scaling might be your best option if you have a limited budget and need to swiftly & inexpensively add more capacity to your infrastructure.
- Future-proofing: By horizontally scaling, you can improve the performance ceiling for your business by adding more modern equipment. A single node can only be vertically scaled so far, and it might not be able to accommodate future needs.
- Flexibility: Scaling out may be a preferable alternative if you want the flexibility to select the ideal configuration setting whenever you want to optimize performance and efficiency. Because vertical scaling will be constrained to the configurations of that single machine only. It will be more challenging to add or update individual lines of code without affecting the overall application if it is built as one big unit. It’s simpler to decouple and horizontally grow your application to give a more continuous upgrade process.
- Topographic distribution: It is unrealistic to expect all of your clients to access your services from the same server in a single place if you want to have a national or international clientele. To sustain your service level agreement in this scenario, you must horizontally scale your resources.
- Reliability and Redundancy: Your system might be more reliable if horizontally scaled. It ensures that you do not depend on a single machine and increases redundancy. When one machine malfunctions, another one might be able to take over temporarily.
Thus, it can be tough to choose the best between both. But, once you get your objectives clear and are aware of the Horizontal vs vertical scaling factors, you surely can make a wiser decision.
How nOps can help you with Cloud Scalability
Ultimately, the leading determinant is the cloud needs and the cost structure. Without being able to forecast the truer sides of these pillars, every business may eventually fall into the trap of choosing an inappropriate scaling strategy for themselves. Thus, cost estimation should be prioritized. Plus, cloud cost optimization remains a challenge no matter what scaling system you are opting for.
By enabling your company to pinpoint precisely which features and products influence your AWS cost, nOps will help you increase cost predictability and expand more effectively. In addition, nOps help businesses map and observe a thorough breakdown of their cloud spending, from the highest level down to the most fundamental elements.
Automatic cloud management tools like nOps Sharesave can be a lifesaver here. With our ShareSave solution, you can save more by centralizing cloud accounts into a consolidated billing model, providing instant and continuous visibility to change requests and delta to your infrastructure that cause cost, and giving you the best root cause analysis capabilities available anywhere.
