Netflix's engineering blog on Medium describes its work on performance, streaming data, machine learning libraries and open source tools.
Commenters share its posts such as Performance Under Load and Vectorflow, and list it among favorite engineering blogs; one complains about Medium paywalls.
I think their point is basically "It doesn't matter" - any client that sends a request which then gets rejected automatically retries and is bound to get a server that is up and has capacity. The retry happens so fast that even with just a naive retry implementation, the end-user won't even notice the interruption.
From https://medium.com/@NetflixTechBlog/performance-under-load-3e6fa9a60581
> The discovered limit and number of concurrent requests can therefore vary from server to server, especially in a multi-tenant cloud environment. This can result in shedding by one server when there was enough capacity elsewhere. With that said, using client side load balancing a single client retry is nearly 100% successful at reaching an instance with available capacity. Better yet, there’s no longer a concern about retries causing DDOS and retry storms as services are able to shed traffic quickly in sub millisecond time with minimum impact to performance.
Edit: In terms of how they decide what to reject, from reading the blog post, there is a queue and there is a limit to how big the queue can be. Requests that come in while the queue is "full" get rejected immediately. They don't wait in the queue and timeout.
I've been looking for a reason to dig into this tool. For those who haven't heard of RiskQuadrant, Netflix put out an article about the project about two weeks ago: https://medium.com/@NetflixTechBlog/open-sourcing-riskquant-a-library-for-quantifying-risk-6720cc1e4968. The project itself is at: https://github.com/Netflix-Skunkworks/riskquant.
I find that medium is even moving articles behind paywall even without consent from author. It was not happening earlier. For example - Look at Netflix Medium blog https://medium.com/@NetflixTechBlog
There are few stories which are behind paywall. Do you think Netflix would have marked them explicitly behind paywall to earn money from blog?
The blog post announcing this might be a better read:
https://medium.com/@NetflixTechBlog/performance-under-load-3e6fa9a60581
(And while reading that and thinking "I swear I recently read something else talking about applying TCP congestion control to RPC queueing". And indeed I had: http://www.evanjones.ca/prevent-server-overload.html)
A few I like on top of what has already been mentioned:
http://rachelbythebay.com/w/
http://highscalability.com/
https://medium.com/@NetflixTechBlog
https://medium.com/@NetflixTechBlog/introducing-vectorflow-fe10d7f126b8