Resource credit pools for replenishing instance resource credit balances of virtual compute instances

A method, comprising:

• performing, by one or more computing devices:
• maintaining a resource credit pool comprising a plurality of resource credits available to replenish an individual resource credit balance for one or more virtual compute instances implemented as part of a provider network, wherein the one or more virtual compute instances are authorized to obtain resource credits from the resource credit pool, wherein the plurality of resource credits are individually expendable to increase utilization of a physical computer resource at a virtualization host implementing one of the one or more virtual compute instances in excess of a utilization guarantee for the physical computer resource until the resource credit is expended;
• receiving a resource credit request for a virtual compute instance of the one or more authorized virtual compute instances to replenish the individual resource credit balance for the virtual compute instance;
• in response to receiving the resource credit request:
• determining a number of resource credits to add to the individual resource credit balance for the virtual compute instance;
• sending a response indicating the number of resource credits to be added to the individual resource credit balance for the virtual compute instance;
• and
• updating the resource credit pool to remove the number of resource credits from the resource credit pool.

A non-transitory, computer-readable storage medium, storing program instructions that when executed by one or more computing devices cause the one or more computing devices to implement:

• maintaining a resource credit pool comprising a plurality of resource credits available to replenish an individual resource credit balance for one or more virtual compute instances implemented as part of a provider network, wherein the one or more virtual compute instances are authorized to obtain resource credits from the resource credit pool, wherein the plurality of resource credits are individually expendable to increase utilization of a physical computer resource at a virtualization host implementing one of the one or more virtual compute instances in excess of a utilization guarantee for the physical computer resource until the resource credit is expended;
• receiving a resource credit request for a virtual compute instance of the one or more virtual compute instances to replenish an individual resource credit balance for the virtual compute instance;
• in response to receiving the resource credit request:
• identifying a number of resource credits to add to the individual resource credit balance for the virtual compute instance;
• sending a response indicating the number of resource credits to be added to the individual resource credit balance for the virtual compute instance;
• and
• updating the resource credit pool to remove the number of resource credits from the resource credit pool.