What is preemptive instance

Preemptive Instance characteristic

Preemptive instances are characterized by large price floating discounts and interruption recovery.

Large price fluctuation discount

• The market price of preemptive instances will fluctuate with supply and demand. Compared with pay as you go instances, it can save up to 90% of instance costs.

• If you set an indefinite usage duration for a preemptive instance, it will be more favorable than a preemptive instance that uses one hour.

explain

The following takes the instance ecs.hfg5.8xlarge in East China 1 (Hangzhou) as an example. The original price of pay as you go instances and the discount of preemptive instances may change. The price is subject to the purchase page. Here is only an example.

Interrupt recycle

The preemptive instance has an interruption recovery mechanism, which is related to the market price, the instance inventory, the upper limit price of a single instance set when creating the instance (that is, the bidding mode), and the duration of the instance 。

If set Set the instance to use for 1 hour After creation, Alibaba Cloud will ensure that the instance will not be released after running for one hour. After more than an hour, the system automatically compares the bid with the market price and checks the resource inventory to determine the instance holding and recovery.

• When offer ≥ market price And keep a large stock of goods Hour ， The instance is running normally.

• When offer < market price or Insufficient inventory Hour ， The instance is interrupted, enters the status of being recycled, and sends a notification of being recycled. It will be automatically released 5 minutes later.

  explain

  offer : Related to the set ceiling price of a single instance (i.e. bidding mode), it is the highest price you are willing to pay for the selected preemptive instance (not the actual billing price):

  • Use Auto Bid : Bid=market price.

  • Set the price limit on a single platform : Bid=the set price ceiling for a single machine. The higher the price, the greater the chance of holding the preemptive instance for a long time.

Applicable scenarios

• Applicable scenarios

  Preemptive instances are applicable to business scenarios that are stateless, fault tolerant, and highly tolerant of interruptions. Typical scenarios are as follows:

  • Real time analysis service

  • Big data business

  • Geospatial survey and analysis business

  • Image and media coding service

  • Scientific computing business

  • Resilient business sites, web crawler services

  • Test business

• Not applicable scenario

  Do not select preemptive instances for services that require long time operation or high stability requirements.

Restrictions on use

• Preemptive instances do not support conversion to subscription instances.

• Preemptive instances do not support changing instance type and bandwidth.

• Preemptive instances do not support filing services.

Billing rules

The price of preemptive instances changes in real time with the supply and demand relationship of the market. For specific billing rules, see Preemptive Instance 。

Instructions

• Create preemptive instance

• Query preemptive instance interrupt events

• Stop preemptive instance

• View preemptive instance bills

• Best practices for data recovery when preemptive instances are recycled

common problem

• What resources are included in the price discount of preemptive instances?

  Only the price of the instance type is discounted. The price of cloud disk, network bandwidth and other resources is not discounted, and is consistent with the price of pay as you go instances.

• Will there be notification when the preemptive instance is released?

  Will be notified. When the preemptive instance needs to be released due to market price changes or supply and demand adjustments, the instance will first enter the status of waiting for recovery, and will be automatically released after about 5 minutes.

• Does preemptive instance support changing instance type?

  I won't support it.

• In terms of price, which one is more favorable for preemptive instances with a duration of one hour or those without a certain duration?

  In order to protect your interests, preemptive instances with uncertain usage duration are always more favorable than those with one hour usage duration.

• Does the switch have protection period and no protection period?

  I won't support it. The preemptive instance has a protection period of 1 hour by default. You can only set the protection period when creating the preemptive instance. You cannot change the protection period setting after creation.

• In terms of release rate, is the preemptive instance without protection period higher than the preemptive instance with protection period?

  You can view the release rate of specific instance types on the sales page, which is applicable to both protected and unprotected instances. The release rate is mainly determined by the supply and demand relationship and bidding strategy of the instance type.

For more questions about preemptive instances, see Instance FAQ 。