Rarefied Data: The Key Factor in Amazon Prime Video’s Transition from Serverless to Monolithic Architecture
In recent news, Amazon Prime Video has made headlines for shifting its video quality analysis team’s architecture from a distributed serverless architecture to a monolithic one, resulting in a 90% reduction in cloud infrastructure costs. This transition saw the team consolidate a diverse array of distributed microservices handling video/audio stream analysis processes into an architecture with all components running inside a single Amazon ECS task.
While this has sparked an intense debate within the tech community about the merits and drawbacks of serverless and monolithic architectures, the core issue behind this transition lies not in the binary argument of serverless vs. monolithic, but rather in understanding the importance of rarefied data and data locality when choosing an appropriate architecture.
In this article, we will explore the concepts of rarefied and dense data, discuss the principles of data locality, and analyze the lessons we can learn from Amazon Prime Video’s transition to create more efficient and cost-effective solutions.

Understanding Rarefied Data and Dense Data
When dealing with various types of data, it is crucial to distinguish between rarefied value data and dense value data. In my data valorization courses that I deliver to companies, I often emphasize the importance of understanding these two types of data and how they impact the design of efficient and cost-effective architectures.
In the case of Amazon Prime Video, the video quality analysis team’s initial serverless architecture encountered abnormal costs in handling large volumes of video and audio data, which can be considered as rarefied value data. These data types require a large amount of storage space, but their individual value is comparatively low. In contrast, dense value data, such as rows in a CRM database, have a high $/GB value, signifying that the individual pieces of data carry a substantial value relative to the storage space they occupy.
This difference in data value has a significant impact on how we process and handle these types of data. For rarefied value data, it is often more efficient to perform in-place processing, as moving the data around can lead to high costs and inefficiencies. On the other hand, dense value data can warrant transportation to the location where computation will occur, as their high value justifies the cost of moving the data.
Recognizing the distinction between rarefied and dense data is essential in determining the best approach for processing and handling data, as well as designing efficient and cost-effective architectures. By sharing these insights in my courses, I aim to help companies make informed decisions when it comes to managing their data assets.
Data Locality and Efficient Architectures
The concepts of “data locality” and “bring computation closer to data” play a vital role in designing efficient architectures for handling various types of data. Data locality emphasizes the importance of minimizing data movement, particularly when dealing with large volumes of data. This concept was a fundamental aspect of big data architectures, most notably Hadoop. However, with the advancements in network efficiency and the scalability of cloud storage, the focus on data locality has diminished to some extent.
In the case of Amazon Prime Video’s video quality analysis team, the initial serverless architecture did not adequately account for data locality principles. Consequently, the team experienced inefficiencies and increased costs due to the unnecessary movement of large volumes of video and audio data. By transitioning to a monolithic architecture, which processes the data in place, the team was able to take advantage of data locality principles and achieve a 90% reduction in cloud infrastructure costs.
Understanding data locality and designing architectures that prioritize cost-effective access to data is crucial for both serverless and monolithic systems. By focusing on the nature of the data being handled and the lessons learned from big data architectures like Hadoop, we can optimize our approaches to create more efficient, cost-effective solutions for a wide range of applications.
Lessons from Amazon Prime Video’s Transition
The recent transition of Amazon Prime Video’s video quality analysis team from a distributed serverless architecture to a monolithic one provides valuable insights for the tech industry. It is important to note that the software engineers at Amazon Prime Video cannot be faulted for their initial serverless implementation. Serverless architecture is fantastic for rapidly creating scalable services; however, once that goal has been achieved, it is natural and necessary to analyze and decide how to optimize the entire system.
In their specific case, the primary issue in the serverless implementation was the lack of consideration for data locality and the cost of accessing data. Consequently, the team incurred unnecessary expenses by moving large amounts of video and audio data around instead of processing it in place. The transition to a monolithic architecture allowed the team to take advantage of data locality principles, resulting in a 90% reduction in cloud infrastructure costs.
The lesson we can learn from this case is the importance of understanding data locality and designing architectures that prioritize cost-effective access to data, whether serverless or monolithic. By adapting our approaches based on the nature of the data we handle and accounting for data locality, we can create more efficient and cost-effective solutions for a wide range of applications.
In conclusion, the debate between serverless and monolithic architectures should not overshadow the need to focus on data locality and the cost of accessing data. By incorporating these principles into our architectural decisions, we can ensure that our systems are optimized for performance, efficiency, and cost-effectiveness, regardless of the specific architecture we choose. It is crucial to continuously assess and optimize our systems based on their unique needs and requirements, as demonstrated by the Amazon Prime Video team.