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Comment by vasco | Hacker News Reader

Of course there's infinite capacity. A google datacenter is infinite capacity from the perspective of say an NTP server. Infinites exist when you have enough orders of magnitude in the middle.

Also traffic isolation and degradation by tier is not "no outage", you're still in outage land, you're just being smart in how you use it and choosing what you disrupt. It doesn't fix the lack of capacity.

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Google's (or any similar large company's, really) efficiency requirements would never allow for such levels of waste. It would be incredibly irresponsible to allow just any random small server to unexpectedly use the entirety (or even just a non-trivial percentage) of a Google-scale datacenter's capacity. Do you evict other jobs? Do you run your datacenters cold to prepare for this eventuality? Both are terrible options.

Suddenly you push an update to your tiny server or one of its thousands of clients and, because of some bug or misconfiguration, traffic or per-request-resource-consumption grows 1000X or more. Given the size of the looong tail of small servers at Google, this would be a daily occurrence.

I don't understand your comment. A google data center is much larger than an ntp server, but it's obviously not infinitely larger. As you know, if it was infinite capacity, then there would be no need for load balancing or load shedding.

And of course, load shedding low priority traffic is still a partial outage, it's just a less bad outage than load shedding high priority traffic. It does not fix lack of capacity, but it significantly lessens the negative effects of it.

It is infinitely larger, because there is no distinction between more than you use, and infinity.

Sure there is infinite capacity given an infinite amount of time to scale up. I assert you’re leaving out the time dimension. Those so-called infinities are simply not accessible in a practical way since you’ll hit a wall in actually provisioning that capacity long before the data center runs out of compute.

You understand it if you think of engineering infinites rather than mathematical infinites. The capacity of a full single datacenter can be treated as infinite for most customers. I explained how its defined in the original comment. Amount of places in engineering where you treat even a 3 order of magnitude difference as infinite is a lot, but the number of order of magnitudes varies depending on context.

Maybe if you're the only customer, but it seems you've not yet gotten a "no capacity" error from AWS, which happens sometimes.

You don't have a single Google datacenter (or any other provider / big name) for a single tenant. The bigger the DC, the more the number of tenants/customers reaches "infinity" (giving the same meaning to "infinity" you are giving to it)

No customer has access to an appreciable fraction of any data center, and if they do they don't have 10x overhead in reserved quota.

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