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Can someone explain Google Preamble Instances vs Amazon Spot Instances? The author says Sutherland was dissuaded by having to specify a spot price upfront on A

by throwaway2016a 10y ago

Can someone explain Google Preamble Instances vs Amazon Spot Instances? The author says Sutherland was dissuaded by having to specify a spot price upfront on AWS but I don't see how that is any different than what Google is doing.

kyrra 10y ago
Looks like there are a number of differences: https://www.quora.com/What-are-the-key-differences-between-AWS-Spot-Instances-and-Googles-Preemptive-Instances https://www.quora.com/What-are-the-key-differences-between-A...
user5994461 10y ago
AWS Spot Instances are under bid. The highest bidder takes the instances, the price changes all the time. Google Spot Instances (preemptibles) are 80% off and that's it. It's simple.
- throwaway2016a 10y ago
  That does sound pretty nice.
- jfroma 10y ago
  We run specific components of our application in spot instances across different regions and from what I have seen in the last 3 months is that the price is generally much less than 80%. I'd say is less than 20% most of the time, but some times there is a peak and it goes beyond 150% for 1 to 3 hours, the frequency of these events may vary but I'd say once a week. I think AWS might be cheaper in this regard but less predictable, so it is a tradeoff. Edit: I haven't looked yet into "Spot Fleets".
  - joshuamorton 10y ago
    Not 80%, 80% off.
    - jfroma 10y ago
      Wops, sorry for my confusion! Then it is definitely interesting :)
  - vacri 10y ago
    Looking at the spot prices on our AWS account (us-east-1), most of the time you're looking at around 25% full price. Some instance types seem to go lower than this (r4 is about 12%) but it looks like the 'resting point' is around 25% for the ones I skimmed.
- takeda 10y ago
  Can't you just bid for 20% of the original price and get the same behavior? In AWS you simply tell how much you're willing to pay to keep the instance uninterrupted. If there's someone who is willing to pay more, they will get the instance from you and yours will be shut down.
  - jjn2009 10y ago
    The main factor is the market for this unused CPU time, a bid of 20% could be vastly different on each service. The GCE pricing model in a way has a sort of step function applied to the pricing, whereas AWS you can bid however you like, how this effects consumer usage I would guess is higher cost on AWS due to perceived competition. This is all assuming the CPU time on machines is constant.
  - Eridrus 10y ago
    AWS also tends to have different prices in different regions and for different sized machines, so there's more work involved in making your 20% work.
  - boulos 10y ago
    With Spot, if the market price goes above .2x retail, and your job runs long enough then you never succeed with Spot. By comparison, if you are able to create a preemptible VM you are guaranteed to pay .2x retail and then likely (but not guaranteed) to have 24h to do your work. tl;dr: A maximum bid of .2x retail isn't equivalent to preemptible. There's almost certainly a bid for a given instance for a given runtime that would result in the same price, but it varies over time, space, runtime and instances shape. Disclosure: I work on Google Cloud (and launched preemptible VMs)
    - williamstein 10y ago
      > likely (but not guaranteed) In my several years experience using GCE it is indeed extremely likely. Two years ago it wasn't very likely, but it became very likely about a year ago. Incidentally, I'm the guy that convinced Drew Sutherland of this article to use GCE in the first place :-).
deleted 10y ago
[deleted]
jacques_chester 10y ago
Preemptibles are at a fixed discount to the normal rate. Spot instances fluctuate according to demand. That said, there is still a "market" here: your work vs Google's work. It just shows up as a private floating probability instead of a public floating price. Most of the time you get the full 24 maximum window. edit: wording
- boulos 10y ago
  Just a small correction: it's not about "your work vs Google's", it's about regular VMs versus preemptible. There's no special code to give Googlers (or Alphabet Characters) special treatment with regards to preemption. The chrome clusterfuzz folks are standing side by side with you. Disclosure: I work on Google Cloud (and launched Preemptible VMs).
  - richardw 10y ago
    Great answers, thank you. Economically, because the price is fixed and everyone has the same status, wouldn't that have the effect of oversubscription if that price is always below amazon spot price? Are you eg legally prevented from using a spot-like bid? I'd imagine spot would balance supply and demand better.
    - jacques_chester 10y ago
      My suspicion is that Google's unit economics for compute and network are better than Amazon's, because they've never historically had the ability to push costs onto a customer. It all fell to their own bottom line. If they can sustain a lower price, picking a fixed discount gives them a marketing edge, even if AWS would come out lower overall. Most humans will pay a premium for certainty -- the certainty effect or "taxicab effect".
      - boulos 10y ago
        There are certainly particular instances in particular regions or zones that are cheaper than the preemptible price we've set. If you look at larger instances, we often are drastically cheaper. Add in the per-minute versus per-hour pricing, and some customers have seen massive wins (I recall one at nearly 10x less). The distinction, as you've surmised, is that predictability is awfully useful. This 220k run (and Drew's quick 400k run last Sunday) had a predictable price. I doubt that such a run on Spot would have left the market price untouched ;). That said, we absolutely have excess capacity that maybe having an auction clearing mechanism would fill. But I don't think it's worth the customer pain. Moreover, even Drew has come to us from Spot, suggesting that simplicity at a usually-fair/good price can take market share away (and reminder this is a fast growing market!).

kyrra 10y ago

Looks like there are a number of differences: https://www.quora.com/What-are-the-key-differences-between-AWS-Spot-Instances-and-Googles-Preemptive-Instances https://www.quora.com/What-are-the-key-differences-between-A...

user5994461 10y ago

AWS Spot Instances are under bid. The highest bidder takes the instances, the price changes all the time. Google Spot Instances (preemptibles) are 80% off and that's it. It's simple.

throwaway2016a 10y ago
That does sound pretty nice.
jfroma 10y ago
We run specific components of our application in spot instances across different regions and from what I have seen in the last 3 months is that the price is generally much less than 80%. I'd say is less than 20% most of the time, but some times there is a peak and it goes beyond 150% for 1 to 3 hours, the frequency of these events may vary but I'd say once a week. I think AWS might be cheaper in this regard but less predictable, so it is a tradeoff. Edit: I haven't looked yet into "Spot Fleets".
- joshuamorton 10y ago
  Not 80%, 80% off.
  - jfroma 10y ago
    Wops, sorry for my confusion! Then it is definitely interesting :)
- vacri 10y ago
  Looking at the spot prices on our AWS account (us-east-1), most of the time you're looking at around 25% full price. Some instance types seem to go lower than this (r4 is about 12%) but it looks like the 'resting point' is around 25% for the ones I skimmed.
takeda 10y ago
Can't you just bid for 20% of the original price and get the same behavior? In AWS you simply tell how much you're willing to pay to keep the instance uninterrupted. If there's someone who is willing to pay more, they will get the instance from you and yours will be shut down.
- jjn2009 10y ago
  The main factor is the market for this unused CPU time, a bid of 20% could be vastly different on each service. The GCE pricing model in a way has a sort of step function applied to the pricing, whereas AWS you can bid however you like, how this effects consumer usage I would guess is higher cost on AWS due to perceived competition. This is all assuming the CPU time on machines is constant.
- Eridrus 10y ago
  AWS also tends to have different prices in different regions and for different sized machines, so there's more work involved in making your 20% work.
- boulos 10y ago
  With Spot, if the market price goes above .2x retail, and your job runs long enough then you never succeed with Spot. By comparison, if you are able to create a preemptible VM you are guaranteed to pay .2x retail and then likely (but not guaranteed) to have 24h to do your work. tl;dr: A maximum bid of .2x retail isn't equivalent to preemptible. There's almost certainly a bid for a given instance for a given runtime that would result in the same price, but it varies over time, space, runtime and instances shape. Disclosure: I work on Google Cloud (and launched preemptible VMs)
  - williamstein 10y ago
    > likely (but not guaranteed) In my several years experience using GCE it is indeed extremely likely. Two years ago it wasn't very likely, but it became very likely about a year ago. Incidentally, I'm the guy that convinced Drew Sutherland of this article to use GCE in the first place :-).

deleted 10y ago

[deleted]

jacques_chester 10y ago

Preemptibles are at a fixed discount to the normal rate. Spot instances fluctuate according to demand. That said, there is still a "market" here: your work vs Google's work. It just shows up as a private floating probability instead of a public floating price. Most of the time you get the full 24 maximum window. edit: wording

boulos 10y ago
Just a small correction: it's not about "your work vs Google's", it's about regular VMs versus preemptible. There's no special code to give Googlers (or Alphabet Characters) special treatment with regards to preemption. The chrome clusterfuzz folks are standing side by side with you. Disclosure: I work on Google Cloud (and launched Preemptible VMs).
- richardw 10y ago
  Great answers, thank you. Economically, because the price is fixed and everyone has the same status, wouldn't that have the effect of oversubscription if that price is always below amazon spot price? Are you eg legally prevented from using a spot-like bid? I'd imagine spot would balance supply and demand better.
  - jacques_chester 10y ago
    My suspicion is that Google's unit economics for compute and network are better than Amazon's, because they've never historically had the ability to push costs onto a customer. It all fell to their own bottom line. If they can sustain a lower price, picking a fixed discount gives them a marketing edge, even if AWS would come out lower overall. Most humans will pay a premium for certainty -- the certainty effect or "taxicab effect".
    - boulos 10y ago
      There are certainly particular instances in particular regions or zones that are cheaper than the preemptible price we've set. If you look at larger instances, we often are drastically cheaper. Add in the per-minute versus per-hour pricing, and some customers have seen massive wins (I recall one at nearly 10x less). The distinction, as you've surmised, is that predictability is awfully useful. This 220k run (and Drew's quick 400k run last Sunday) had a predictable price. I doubt that such a run on Spot would have left the market price untouched ;). That said, we absolutely have excess capacity that maybe having an auction clearing mechanism would fill. But I don't think it's worth the customer pain. Moreover, even Drew has come to us from Spot, suggesting that simplicity at a usually-fair/good price can take market share away (and reminder this is a fast growing market!).