US 2015/0317179 A1 · EFFICIENT INPUT/OUTPUT-AWARE MULTI-PROCESSOR VIRTUAL MACHINE SCHEDULING

Abstract

Computerized methods, computer systems, and computer-readable media for governing how virtual processors are scheduled to particular logical processors are provided. A scheduler is employed to balance a CPU-intensive workload imposed by virtual machines, each having a plurality of virtual processors supported by a root partition, across various logical processors that are running threads and input/output (I/O) operations in parallel. Upon measuring a frequency of the I/O operations performed by a logical processor that is mapped to the root partition, a hardware-interrupt rate is calculated as a function of the frequency. The hardware-interrupt rate is compared against a predetermined threshold rate to determine a level of an I/O-intensive workload being presently carried out by the logical processor. When the hardware-interrupt rate surpasses the predetermined threshold rate, the scheduler refrains from allocating time slices on the logical processor to the virtual machines.

Claims20

Dependent claims

One or more computer-readable media having computer-executable instructions embodied thereon that, when executed, perform a method for excluding one or more virtual processors from being scheduled to a logical processor, the method comprising:

monitoring over a window of time a pattern of input/output (I/O) operations performed by a root partition, wherein the logical processor is mapped to root partition and is designated to carry out I/O operations issued thereby;
deriving an I/O-awareness variable a function of the pattern of I/O operations;
based on the I/O-awareness variable, refraining from scheduling tasks issued from the one or more virtual processors onto the logical processor;
and
at least temporarily storing the I/O-awareness variable at an interrupt table that is accessible by a scheduler.

2 more elements

A computerized method for arresting allocation of a logical processor to one or more virtual processors, the method comprising:

identifying a frequency at which a root partition has acquired a lock on the logical processor, wherein the logical processor is configured to execute input/output (I/O) operations issued by the root partition upon acquiring the lock, and wherein the logical processor is one of a plurality of logical processors that are carved out of a physical machine to execute threads issued by the one or more virtual processors;
ascertaining a hardware-interrupt rate as a function of the identified frequency;
comparing the hardware-interrupt rate against a predetermined threshold rate;
when the hardware-interrupt rate surpasses the predetermined threshold rate, arresting allocation of the logical processor to the one or more virtual processors;
and
when the hardware-interrupt rate resides below the predetermined threshold rate, scheduling the one or more virtual processors to the logical processor.

3 more elements

Dependencies are inferred from the claim text.

Efficient input/output-aware multi-processor virtual machine scheduling

Life of this patent

Efficient input/output-aware multi-processor virtual machine scheduling

Life of this patent

Abstract

Claims20