4 ms·

John is confusing CPU time with CPU-core time. I assume he gets the $0.025/hour figure from "a1.medium", which is 1 core ("vCPU") with 2GB RAM. As a result of

John is confusing CPU time with CPU-core time. I assume he gets the $0.025/hour figure from "a1.medium", which is 1 core ("vCPU") with 2GB RAM. As a result of competition, the price of any service tends toward cost of the service. So a $2000 computer with 8 cores that lasts 4 years + $500 for power/year + $500 for support/year is $1500/year or $0.17/hour. That's $0.021/core/hour, and the difference is a small amount of profit for Amazon and a buffer for when the CPU is idle.

magduf 8y ago
>So a $2000 computer with 8 cores that lasts 4 years + $500 for power/year + $500 for support/year is $1500/year or $0.17/hour. That's $0.021/core/hour, and the difference is a small amount of profit for Amazon and a buffer for when the CPU is idle. The other factor is power. That $500 for power for a year won't be $500 if the CPU is running full-tilt all the time, it'll be much more. Modern CPUs are designed to be power-efficient when idle, and then be able to perform many computations quickly when demanded, even if this actually exceeds the hardware's ability to dissipate heat (in which case the CPU throttles itself to avoid overheating). For computers used interactively by people (i.e., laptops, desktops, but not servers), the workload tends to be extremely bursty, with the CPU doing nearly nothing most of the time waiting for the user to do something, and then suddenly having to do a lot of work quickly when demanded (e.g., rendering a bloated webpage or watching a video). In short, CPU time isn't just being "wasted"; modern CPUs are explicitly designed to be used this way.
- teraflop 8y ago
  Where I live (Texas) electricity costs about $0.08/kWh, which means $500 per year will buy about 700 watts of continuous power. That's much higher than the TDP of any 8-core processor on the market. Even if you have more expensive power and account for cooling costs, it's hard to see how you could end up spending much more than $500/year to power a single machine.
  - magduf 8y ago
    Yeah, I wasn't looking into how realistic that $500 number was, I just accepted it from the OP as a given. But I think electricity tends to be more expensive in other parts of the country.
    - bearjaws 8y ago
      Datacenters are placed wherever energy can be easily and cheaply acquired. Some may negotiate special deals with local utility companies, I don't have hard numbers on what datacenters usually pay for electricity though (assuming they don't provide their own).
  - bzbarsky 8y ago
    Just for comparison, where I am (Massachusetts) it's $0.23/kWh or so for residential service.
    - souprock 8y ago
      It's $0.05 here in Florida. Cost of living is no joke. It's only a penny for the big industrial users.
      - bzbarsky 8y ago
        $0.05 for both generation _and_ transmission charges? I would have expected that to be more like $0.09 or $0.10 for Florida... Still a good bit better than MA, of course. :)
        souprock 8y ago
        There are some extra things, like a fuel charge. It comes to about $0.08 or $0.09 adding those things in, plus about $8 per month just to be connected.
- vortico 8y ago
  Maybe if you're in CA. Most other places in the US are less than $0.14/kWh.

magduf 8y ago

>So a $2000 computer with 8 cores that lasts 4 years + $500 for power/year + $500 for support/year is $1500/year or $0.17/hour. That's $0.021/core/hour, and the difference is a small amount of profit for Amazon and a buffer for when the CPU is idle. The other factor is power. That $500 for power for a year won't be $500 if the CPU is running full-tilt all the time, it'll be much more. Modern CPUs are designed to be power-efficient when idle, and then be able to perform many computations quickly when demanded, even if this actually exceeds the hardware's ability to dissipate heat (in which case the CPU throttles itself to avoid overheating). For computers used interactively by people (i.e., laptops, desktops, but not servers), the workload tends to be extremely bursty, with the CPU doing nearly nothing most of the time waiting for the user to do something, and then suddenly having to do a lot of work quickly when demanded (e.g., rendering a bloated webpage or watching a video). In short, CPU time isn't just being "wasted"; modern CPUs are explicitly designed to be used this way.

teraflop 8y ago
Where I live (Texas) electricity costs about $0.08/kWh, which means $500 per year will buy about 700 watts of continuous power. That's much higher than the TDP of any 8-core processor on the market. Even if you have more expensive power and account for cooling costs, it's hard to see how you could end up spending much more than $500/year to power a single machine.
- magduf 8y ago
  Yeah, I wasn't looking into how realistic that $500 number was, I just accepted it from the OP as a given. But I think electricity tends to be more expensive in other parts of the country.
  - bearjaws 8y ago
    Datacenters are placed wherever energy can be easily and cheaply acquired. Some may negotiate special deals with local utility companies, I don't have hard numbers on what datacenters usually pay for electricity though (assuming they don't provide their own).
- bzbarsky 8y ago
  Just for comparison, where I am (Massachusetts) it's $0.23/kWh or so for residential service.
  - souprock 8y ago
    It's $0.05 here in Florida. Cost of living is no joke. It's only a penny for the big industrial users.
    - bzbarsky 8y ago
      $0.05 for both generation _and_ transmission charges? I would have expected that to be more like $0.09 or $0.10 for Florida... Still a good bit better than MA, of course. :)
      - souprock 8y ago
        There are some extra things, like a fuel charge. It comes to about $0.08 or $0.09 adding those things in, plus about $8 per month just to be connected.
vortico 8y ago
Maybe if you're in CA. Most other places in the US are less than $0.14/kWh.