Abstract: Systems and methods are described for reclamation of computing resources in an on-demand code execution system. An on-demand code execution system may execute user-submitted code on virtual machine instances, which may be provisioned with quantities of various computing resources (memory, storage, processor time, etc.). These quantities of computing resources may be unused or underutilized depending on the resource requirements of the user-submitted code, or may become idle once the user-submitted code has completed execution. A resource reclamation system may thus reclaim these underutilized computing resources and reallocate them to other uses. The resource reclamation system may interact with a reclaimable resource identification process that executes within the virtual machine instance, which may identify unused or underused computing resources, claim them, and then allow the resource reclamation system to reallocate them.

Abstract: Systems and methods are described for dynamically adjusting quantities of computing resources allocated to virtual machine instances in an on-demand code execution system. An on-demand code execution system may execute user-submitted code on virtual machine instances, which may be provisioned with quantities of various computing resources (memory, storage, processor time, etc.). Users may request that code be executed on virtual machine instances having a particular quantity of a particular computing resource, and a previously provisioned virtual machine instance have a different quantity of the resource than the quantity requested. A resource reclamation system may thus be used to dynamically adjust the quantity of computing resources without reprovisioning the virtual machine instance.