Is this really realtime?

From looking at the description it sounds more like subscriptions to events of data changes that are dispatched close to the data operation

How would realtime even work for a networked system going over tcp?

https://en.wikipedia.org/wiki/Real-time_computing

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SerCe 3 hours ago | parent | next [-]

I believe there is no contradiction with the definition from the linked article?

> A system is said to be real-time if the total correctness of an operation depends not only upon its logical correctness, but also upon the time in which it is performed. Real-time systems, as well as their deadlines, are classified by the consequence of missing a deadline:

> Hard – missing a deadline is a total system failure.

> Firm – infrequent deadline misses are tolerable, but may degrade the system's quality of service. The usefulness of a result is zero after its deadline.

> Soft – the usefulness of a result degrades after its deadline, thereby degrading the system's quality of service.

From what I can tell, https://pocketbase.io/ attempts to be a soft-realtime system.

	▲	ffsm8 15 minutes ago \| parent [-]
		Really? I couldn't really see anything wrt degraded performance from my casual glance. To me, It looks like there are just best effort events with literally no constraints or handling for delays etc And again, I didn't see how you'd even implement such without being on both sides of the networked connection I guess I just have to accept that the term has lost it's meaning at this point and can be used for whatever whoever wants to use it for

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phplovesong 3 hours ago | parent | prev | next [-]

There is realtime, and there is "realtime". The other one being realtime in apps doing some sort of music thing, flight controllers etc. Then there is web "realtime" that basically only means 2sec in the past-realtime.

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3 hours ago | parent | prev | next [-]

[deleted]

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cess11 3 hours ago | parent | prev | next [-]

It's common to distinguish between hard real-time and soft real-time (and sometimes firm real-time).

This software is supposedly soft real-time, similar to what you'd expect from e.g. an Erlang system. Delayed tasks aren't considered fatal failures but overall you get a user experience close to what hard real-time systems are supposed to deliver.

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zwnow 3 hours ago | parent | prev [-]

Realtime in tech is considered in timespans with short delays allowed, last time i have read about it it was like 100ms.

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anonymousiam 3 hours ago | parent | next [-]

Heh. I wasn't aware that there was a new definition of realtime. My 40+ year career consisted of about 20% realtime embedded firmware development. In all of my experience, 100ms is an absurdly long delay. Most RTOSs (that call themselves such) have latency measured in μs. The last serious RTOS that I wrote (MSP430, non-preemptive) had a firm requirement that any task must complete within 1ms. That one ran on a single threaded MCU clocked at 25MHz. It had a unix-like scheduler, with prioritized tasks, and I even threw in a 'top' display that showed per-task MCU usage, and load average.

	▲	JSR_FDED 2 hours ago \| parent \| next [-]
		Yeah, and I’m using Pocketbase as my game engine and it isn’t giving me 60 frames per second either.
	▲	zwnow 3 hours ago \| parent \| prev [-]
		Well Pocketbase isnt embedded firmware.

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foul an hour ago | parent | prev | next [-]

Are you talking about (very good) webapps?

Your average RT software has an average of 10 to 30 ms delay between operations. Performs tasks in the order of nanoseconds.

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fragmede 3 hours ago | parent | prev [-]

Realtime in tech has a specific definition. The Wikipedia article covers it in more detail, but think about things like airplane wing control or space rocket computers needing to do things exactly when asked, or else people die.

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zwnow 3 hours ago | parent [-]

Even that stuff has a delay.

	▲	anonymousiam 2 hours ago \| parent [-]
		FYI, my above referenced RTOS was for a space-based application.