Extending placement constraints for virtual machine placement, load balancing migrations, and failover without coding

摘要

Techniques are described for placing virtual machines (VM) on computer hosts. In one embodiment, a user may compose a constraint specification document which includes VM and host properties and how they are retrieved, as well as constraint predicates that define valid VM placements on hosts. Use of the constraint specification document permits new constraints, including constraints that involve new properties, to be handled without requiring changing the underlying code for collecting required input data and processing said data to determine whether placement constraints are satisfied. Instead, based on the constraint specification document, a resource scheduler or high availability module may program a programmable data collector to fetch the needed properties from the appropriate places. Then, the resource scheduler or high availability module may parse the constraint predicates, evaluate potential placements to determine whether the constraint predicates are satisfied, and place VMs according to placements that satisfy the constraint predicates.

主权项

1. A method of placing a virtual machine (VM) on a computer host or group of computer hosts, comprising:
parsing a specification file, the specification file specifying properties whose values are to be determined and placement constraints, each placement constraint defining a condition for VM placement on the host or the group of hosts as a function of one or more of the properties; determining values for the properties based on information autonomously collected by one or more programmable data collectors from the host or the group of hosts or from a centralized server which manages the host or the group of hosts, the data collectors operating in accordance with data collection properties specified in the specification file; determining if the placement constraints in the specification file are satisfied using the determined values of the properties; and placing the VM on the host or the group of hosts if the placement constraints in the specification file are satisfied for the placement.