Optimization of virtual machines

A computer program product for providing additional virtual machines to handle increased workloads, the computer program product comprising:

• one or more computer readable storage media;
• and
• program instructions stored on the one or more computer readable storage media, the program instructions comprising:
• program instructions to provide a resource reservoir, wherein the resource reservoir is a pool of resources that are allocated to and shared between a plurality of reserve virtual machines, a reserve virtual machine of the plurality of reserve virtual machines corresponding to a primary virtual machine from a plurality of primary virtual machines, wherein each reserve virtual machine of the plurality of reserve virtual machines fulfills a resource requirement from the resource reservoir, and wherein a sum of the resource requirements of the plurality of reserve virtual machines is greater than a sum of total resources within the resource reservoir;
• program instructions to determine a decrease in performance of the primary virtual machine;
• program instructions to, in response to the decrease in performance of the primary virtual machine, apply at least a portion of workload of the primary virtual machine to the corresponding reserve virtual machine;
• and
• program instructions to, in response to applying at least a portion of the workload to the corresponding reserve virtual machine, indicate that resources used by the reserve virtual machine are unavailable to remaining reserve virtual machines from the resource reservoir.

A computer system for providing additional virtual machines to handle increased workloads, the computer system comprising:

• one or more computer processors;
• one or more computer readable storage media;
• and
• program instructions, stored on the one or more computer readable storage media for execution by at least one of the one or more computer processors, the program instructions comprising:
• program instructs to provide a resource reservoir, wherein the resource reservoir is a pool of resources that are allocated to and shared between a plurality of reserve virtual machines, a reserve virtual machine of the plurality of reserve virtual machines corresponding to a primary virtual machine from a plurality of primary virtual machines, wherein each reserve virtual machine of the plurality of reserve virtual machines fulfills a resource requirement from the resource reservoir, and wherein a sum of the resource requirements of the plurality of reserve virtual machines is greater than a sum of total resources within the resource reservoir;
• program instructions to determine a decrease in performance of the primary virtual machine;
• in response to the decrease in performance of the primary virtual machine, program instructions to apply at least a portion of workload of the primary virtual machine to the corresponding reserve virtual machine;
• and
• program instructions, in response to applying at least a portion of the workload to the corresponding reserve virtual machine, to indicate that resources used by the reserve virtual machine are unavailable to remaining reserve virtual machines from the resource reservoir.