A P0 Failure is the worst failure possible, i.e. drop whatever you are doing and FIX it. In tech-speak, P1 is the second worst failure and the rankings go down to P4 which means: "Noted, this bug is one step away from a black hole." And we all know what black holes do to things that are one step away…
Google DoubleClick "P0" Failure
By JIM EDWARDS at Business Insider
[Picture by USAG- Humphreys]
Google's DoubleClick ad server went down today for about an hour, triggering a rare "P0" response from the company.
People who don't work in tech won't know what "P0" (or "P zero" or "p0") means, but within the software industry, P0 can be loosely defined as "the worst possible thing that can happen."
The ad server is back up and running now, but during its outage about one third of all web sites that carry advertising on planet earth were without ads. Some of them were unable to load their pages properly, and maybe $1 million was lost in ad revenue, collectively, as a result.
As Google's entire business is about serving ads in a completely reliable way, this was bad news.
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Note that P0 isn't just a serious emergency, it's an emergency that is so severe no other work can take place until the bug is fixed. An existential threat, in other words.
Full article: Google DoubleClick "P0" Failure – Business Insider.
