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by PaulDavisThe1st 494 days ago
This has nothing to do with soft realtime, hard realtime or realtime in any of its more traditional senses.

TFA is just about the design and deployment of a two-way ("duplex") communication system that makes distributed applications "feel modern, collaborative, and up-to-date"

These sorts of systems have existed for decades; TFA provides a brief overview of 3 design patterns associated with them.
2 comments
cowboy_henk 493 days ago
The wikipedia page on real-time seems to agree with OP that this would be a soft real-time system: https://en.wikipedia.org/wiki/Real-time_computing

In particular

> Soft real-time systems are typically used to solve issues of concurrent access and the need to keep a number of connected systems up-to-date through changing situations

That's exactly what this post is about. "Real-time" on the web often just means an app that allows multiple users to concurrently make updates to some piece of state, and for the changes to that state to be broadcast to all users so that all clients are kept consistent within a reasonable time frame, preferably as quickly as possible.

While the deadlines aren't as hard as in e.g. audio programming, "real-time multiplayer" apps can be said to be broken if there is a very large noticeable delay between a user editing something and the other users seeing that edit reflected in their local client.

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MisterTea 493 days ago
> "Real-time" on the web often just means an app that allows multiple users to concurrently make updates to some piece of state, and for the changes to that state to be broadcast to all users so that all clients are kept consistent within a reasonable time frame, preferably as quickly as possible.

Hard disagree. There is no deadline to meet time wise, only that a specific task must be completed in a specific order as quickly as possible. This implies managing state while keeping latency low which is a QoS problem.

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MisterTea 493 days ago
> This has nothing to do with soft realtime, hard realtime or realtime in any of its more traditional senses.

Agreed. The best term to use for this scenario is low-latency as real time implies a deadline. low-latency deals with QoS where you ascribe a quality parameter to the service.

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