Is "brownout" a common or standard term in the industry? First time I see it.

Commonly used in microcontrollers to describe supply voltage dropping below threshold. It could cause RAM corruption, erratic behaviors of robots, overshoot in voltage regulators, battery fluid leaks etc., and so optional detection features are often made available to reset or stop the processor and notify the application on next boot.

It's also used in utility power supplies to describe line voltage going below spec. It's considered a dangerous condition in that context too, as lots of non-smart equipment tend to run at higher amperage at lower voltage and/or fail to start/run and catch fire.

1: https://developerhelp.microchip.com/xwiki/bin/view/products/...

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habitue 5 days ago | parent | prev | next [-]

We did this at stripe when deprecating TLS 1.0, and called it a brown out (I don't know the origin of the term in software).

You do it when you have a bunch of automated integrations with you and you have to break them. The lights arent on at the client: their dev teams are focused on other things, so you have to wake them up to a change that's happening (either by causing their alerting to go off, or their customers to complain because their site is broken)

	▲	dkdcio 5 days ago \| parent [-]
		have also heard this as doing a “scream test” — turn it off, see who screams about it

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Beltran 5 days ago | parent | prev | next [-]

Yes, another example of brownout at https://spring.io/blog/2022/12/14/notice-of-permissions-chan... It is probably the only way to warn users when you do not know the contact info.

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01HNNWZ0MV43FF 5 days ago | parent | prev | next [-]

Yes I heard of GitHub doing it I think

You intentionally break something just a little to force dependents to notice, before turning it off completely

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usrme 5 days ago | parent | prev | next [-]

There was actually a really terrible brown-out by Poetry (a Python dependency management and packaging tool) where they introduced sporadic failures to people's CI/CD systems: https://github.com/python-poetry/poetry/pull/6297

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aabhay 5 days ago | parent | prev | next [-]

First heard about this when docker started rate limiting

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miki123211 5 days ago | parent | prev | next [-]

Yes.

It refers to a situation where a system is deliberately designed to fail (usually for short periods of time), to still provide some level of service while alerting others that the system is soon to be turned off.

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znpy 5 days ago | parent | prev [-]

Yes. Going from green to red is called “browning out”.

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jacquesm 5 days ago | parent | next [-]

That is not where the term comes from. Lights out -> Blackout (WWII, to stop overflying aircraft from having easy targets and to disrupt navigation). Reduced voltage on the grid -> lights go from white to orange and eventually to brown, not quite a blackout -> brown out.

	▲	mattkrause 4 days ago \| parent [-]
		The word seems to slightly predate WWII. The OED reports that the disrupted-electrical supply sense of blackout was first used in 1934; the air-defence one (no light) in 1935. However, the OG use seems to be in the theatre, where the lights are shut off during set changes (1913, probably earlier). Brownout does seem to be a WWII-era term, but more related to conservation/shortages than air defence.

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mattkrause 5 days ago | parent | prev [-]

Is that the origin?

I thought it was an analogy to the electrical problem: flickering lights due to high demand.

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wafflemaker 5 days ago | parent [-]

Don't know the origin, but with no technical background past using Linux, I only ever heard of brownouts in contexts of failing (often 3rd world) electrical infrastructure. Mostly Africa and South America (don't mean to offend anybody living there, I know they're vast continents with many rich/infrastructure-stable countries too).

	▲	lstodd 5 days ago \| parent \| next [-]
		Origin is the electrical grid overload which caused incandescent lights to literally "brown out", as has been mentioned here. Later is was coopted to mean any problems with power supply not including outright drop to zero-zero/disconnections. cf microcontroller brown-out handling, also mentioned above. Then later it seems it was generalized to mean sort-of-non-terminal problem with supply of most anything.
	▲	lagniappe 4 days ago \| parent \| prev [-]
		Very odd to call it a 3rd world phenomenon when California calls it a normal day.