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GCP releases Spot VMs, the next generation of Pre-emptible VMs

cloud.google.com

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Re: GCP releases Spot VMs, the next generation of Pre-emptible VMs

#51

Post by apendleton »

xyzzyz wrote: post #37
roca wrote: post #20

Earlier quoted context omitted.

Just spin up regular VMs if you can't get spot instances when you need them.

Lack of spot VM means that all spare capacity has been taken up by the regular VMs, meaning that it spots are gone, so are regular ones.

Having worked on infrastructure deployed this way, I can say this oversimplifies a bit. There's virtually never no spot capacity at all, there's no capacity at a given bid price, for a given instance type, in a given region. You can start to scale up on-demand infrastructure using spot price as a signal, before there's literally none left, and you can also run on clusters of heterogeneous instances, and change your instance type mix when one instance type's price goes up. In the worst case you can fail out of a particular region whose spot prices have gotten too high. Lots of options.

Re: GCP releases Spot VMs, the next generation of Pre-emptible VMs

#54

Post by dragonwriter »

travisd wrote: post #3

I don’t see this in the article, but is there any reason why they’d introduce a new VM type rather than just removing the 24hour limit of preemptible VMs?

Preemptible VMs are GA, Spot VMs are not; if there are changes that might be made to Spot before GA (such as other limits, etc.), this gives them the freedom to do that, without impacting those using Preemptible.

Re: GCP releases Spot VMs, the next generation of Pre-emptible VMs

#55

Post by ur-whale »

So, probably a very naive question here, but how his the "continuity" across pre-emptions working?

Say I am running a long batch process on one of these spot VMs and I get pre-empted ...

Does my job restart where it was stopped automatically and everything is transparent save how long the job takes to complete, or do I have do to checkpointing myself and deal with the fact that my jobs may be killed at anytime?

Also, if the restarts are indeed transparent to my job, what of stateful network connections?

Finally, what kind of guarantee do I have that my job will ever complete if pre-emption can happen at an arbitrary frequency for arbitrarily long?

Re: GCP releases Spot VMs, the next generation of Pre-emptible VMs

#56

Post by ramoz »

titzer wrote: post #7

I have trouble thinking of a use case that fits this VM type. Is it for batch processing tasks that don't have tight deadlines? The lack of any real guarantees makes it hard to price, as you have no idea what you're actually paying for. Would it make sense to have a model that includes deadlines in its pricing (like give this process 2.5 hours of CPU and 4GB of RAM to complete this task by...next Tuesday)?

My team runs fairly large GKE clusters on preemptible machines, and with a dedicated footprint that can scale if needed. Business critical workloads, we ensure a lot of these https://cloud.google.com/kubernetes-engine/docs/concepts/spo...

cost savings.

Re: GCP releases Spot VMs, the next generation of Pre-emptible VMs

#57

Post by aetherspawn »

mike_d wrote: post #45
aetherspawn wrote: post #30

“requiredDuringSchedulingIgnoredDuringExecution” .. wow, what an epic length for a configuration option!

Let me introduce you to CNLabelContactRelationYoungerCousinMothersSiblingsDaughterOrFathersSistersDaughter https://developer.apple.com/documentation/contacts/cnlabelco...

I doubt the person who released this did it with a straight face.

Re: GCP releases Spot VMs, the next generation of Pre-emptible VMs

#58

Post by ur-whale »

superasn wrote: post #52
gravypod wrote: post #2

Any word on pricing?

Also what is the granularity? Right now on AWS you have to pay for the full hour even if you use it for 5 minutes. A per minute granularity can make Google's offering more enticing for a lot of users.

>Also what is the granularity?

Don't have an authoritative answer, sorry, but granularity is an area where Google has historically been better than the competition.

Re: GCP releases Spot VMs, the next generation of Pre-emptible VMs

#59

Post by ur-whale »

aetherspawn wrote: post #30

“requiredDuringSchedulingIgnoredDuringExecution” .. wow, what an epic length for a configuration option!

>“requiredDuringSchedulingIgnoredDuringExecution” .. wow, what an epic length for a configuration option

Looks like Java culture is alive, well and spreading.

Re: GCP releases Spot VMs, the next generation of Pre-emptible VMs

#60

Post by sudhirj »

ggm wrote: post #50

Is this a sign they have surplus pre-emptible capacity on their architecture for non-premptible VMs, and so worrying, if you think they have enough customers to sustain the model? (google could run negative forever: the point is, some VP won't want to, and the KPI will morph to "kill it")

No, all clouds must overprovision their datacenters to handle sudden peak demand. Everybody doubles or tripes their clusters around the holiday season or shopping festivals, for example. For the other 350 days of the year, this capacity often lies unused - so they're auctioned off to the highest bidder (but usually at spot rates much less than the full rent). They're pre-emptible because if you need the servers for something serious/stable/continuous and make an on-demand rent request, the spot instances are pulled off their workloads and given to you at the full rate.
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