New Spot Pricing System - FAQ
What has changed in the Spot pricing model?
As part of AWS recently announcing a new Spot pricing model, the way we consume Spot Instances has also changed. The two major changes are:
- Bidding is no longer mandatory
- Prices will change less frequently
How is the Spot Market price determined?
The AWS Spot Market price will still be based on supply and demand for EC2 spare capacity. You just won’t be able to see the price changes until after it jumps.
How does AWS determine who will get the capacity allocation?
When multiple customers request Spot Instances, requests will be fulfilled on a first-come, first-served basis.
When AWS reclaim Spot capacity, how do they determine who to evict an Instance?
When AWS has to reclaim Spot capacity its for two reasons, with the primary one being Amazon EC2 capacity requirements (e.g. On Demand or Reserved Instance usage). Secondarily, if you have chosen to set a “maximum Spot price” and the Spot price rises above this, your instance will be reclaimed with a two-minute notification.
Under the new pricing system, how can we know the availability of certain instance types in the spot market?
If you were using the Spot Pricing history to determine availability, with the new change you can simply no longer use that approach. In the new pricing system, Spot Market prices do not reflect immediate supply and demand in the market. While customers can still use the API to get the current pricing, this data does not reflect the actual market state Spotinst, however, can reflect the actual market state using its advanced algorithms that analyze the Spot Market history for the last 3 years.
Does the new EC2 Spot pricing model impact what I actually pay?
No. The pricing model has changed but the principles remain the same. Spotinst’s Elastigroup will continue to run your workloads on long-living, cost-effective Spot markets and will ensure you get the best rates.
How can I know which markets to choose now that the prices aren’t updated as frequently with AWS?
We advise our customers to always select as many markets as possible. Elastigroup will then have the flexibility to choose the best fit for the requested capacity, taking into consideration both the lifetime of the instance and its pricing (both current and future pricing).
Spot Bids & Interruptions
We bid more than the OD price today to ensure availability, how can we ensure we will get capacity if the bid price is optional?
Spotinst will use its advanced prediction algorithms to detect anomalies in the Spot Market, ensuring that your service remains available at all times.
Will Spot prices go above On-Demand? Will they ever reach to 10X On-Demand?
Yes. Just as before, Spot prices may exceed the On-Demand price.
How do this change effect Spotinst and Spotinst customers?
For our customers, there is no change. We adjusted anything necessary under the hood. That said, the change doesn’t really affect the way Spotinst Elastigroup operates. Bidding and price changes frequency weren’t important at any time. Spotinst uses advanced prediction algorithms that analyze data from the last 3 years in scales of millions of instances to detect anomalies in the Spot market. It doesn’t rely on bids, visibility of price changes, or frequency of price changes.
I’m a Spotinst customer. Will this impact my service availability?
No. Spotinst Elastigroup will continue to provide 100% availability and guarantees to provide the same SLA after the Spot pricing model changes.
Does this impact Spotinst’s termination prediction?
No. Spotinst predictions never relied on the frequency of price changes and will continue to provide accurate predictions of the spot market trends.
Does it increase the chances of interruptions when running on Spotinst?
No. Elastigroup detects interruptions in advance and proactively replaces instances gracefully prior to the interruption.
Do I need to make any change to my Elastigroups?
No changes are required in Elastigroup or any other Spotinst service.
In case of capacity shortage, how does Elastigroup keep my service running?
Elastigroup provides 100% availability to your services by predicting the Spot Market trends and acting preemptively to ensure capacity is granted. Features like fallback to on-demand, Availability Zone, and Spot type distribution, and automatic instance replacement allow us to provide a ‘safety net’. Even when there is a shortage of capacity from the cloud provider. This allows us to guarantee 100% availability for any workload.
The hibernate feature in AWS saves data from RAM to the root EBS volume. Does Spotinst do that as well?
Yes, it’s supported by Spotinst as well, All you need to do is to install the agent with the following user-data script.
Which Instance types does the hibernation supports?
The Spot hibernation feature supported on C3, C4, M4, R3, and R4, with less than 122 GB of memory.
Which Operating System does the hibernation supports?
The following operating systems are supported: Amazon Linux AMI, Ubuntu with an AWS-tuned Ubuntu kernel (linux-aws) greater than 4.4.0-1041, and Windows Server 2008 R2 and later.