In this video Josh Evans talks about the chaotic and vibrant world of microservices at Netflix.
He starts with the basics- the anatomy of a microservice, the challenges around distributed systems, and the benefits. Then he builds on that foundation exploring the cultural, architectural, and operational methods that lead to microservice mastery.
Mr. Josh Evans, at 2:24 stresses the importance of the traffic present in a microservices architecture, the traffic spikes, the DDoS attack that can bring changes to the environment causing obstacles for the customers in accessing their service.
At 5:10 he begins by stating the interesting statistical records achieved by Netflix which has now easily become a leader in subscription internet tv service with nearly 86 million members subscribing for the service. At 6:02 he states that Netflix initially had an infrastructure that was hardware oriented and very expensive. He also added that so many changes were happening on a regular basis to the base architecture.
At 8:22 Josh defines microservices to be an architectural approach for developing the single application as a suite of the small services ensuring that each run its own process and communicates via lightweight mechanisms. At 9:38 he emphasizes that separation of concerns that include modularity, encapsulation and the biggest benefits of Netflix microservices that includes scalability and virtualization. At 12:55 Josh explains the way microservices achieve abstraction, the way the EVCache Client send the request which is then processed in the backend database with the help of the server.
At 15:10 he explains an interesting scenario of Cascading Failure wherein one can find one service failing with the improper defenses against the failing service, it cascades which would, in turn, demolish the entire deployed system.
At 18:25 Mr. Josh puts forwards the concept of critical microservices. He defines them to be the ones with the basic functionality work and services that help in managing the highly prioritized and less prioritized functions separately. At 22:29 he begins explaining the CAP Theorem wherein one will have to choose between consistency and reliability. He further adds on that Netflix following the idea of eventual consistency and later working on the flaws.
At 25:01 significant use cases for stateless, stateful and hybrid services are explained by Josh. At 26:03 he explains the stateless service to be the one that has no instance affinity, not a cache or a database and the frequently accessed metadata. He strengthens the concept by explaining the auto scaling groups, the AMI retrieval on demand and how efficiency and node failures are managed at 27:00. He then moves to the concept of stateful service at 27:46 where he defines that to be the custom applications holding an enormous amount of data, the databases and the caches.
At 31:40 he moves to the current trending topic of hybrid microservices wherein excessive load scenarios can be managed well with the hybrid architectural design. He adds on that workload partitioning and the request-level caching technique are employed for hybrid cases.
At 36:33 he explains about the continuous learning and automation technique, where the flow generally begins with the incident, resolution, review, remediation, analysis, best practices, automation, and the adoption. At 40:30 Mr. Josh briefs about the cost of variance and that different productivity tools must be used to reduce the time taken in the case of the containers and the Docker.
At 42.35 he expresses that Netflix recently understood that it was very important to raise awareness of costs so that people are well informed about the architectural designs, its benefits, and tradeoffs. At 47:07 he talks about the Netflix API that turned to be helpful for the company as it helped in figuring out the UI innovation, the metadata, and the generalized REST API JSON schema.
His talk has thus provided great insights on the anatomy of the Netflix microservices, architectural designs, challenges, and the vast benefits.
Download the slides & audio at InfoQ.