Interrupt Delay Mechanism for Virtual Machine Idle State Management

Solution Overview

Problem

Virtual machines wake up unnecessarily when idle, consuming significant computing resources and generating unnecessary network traffic due to immediate interrupts during hot plugging or hot unplugging of devices, which can lead to undesired resource requests and tasks execution.

Innovation Solution

Delaying interrupts for virtual machines until they transition from an idle to an awake state by storing them in an interrupt register, preventing immediate transmission and thus avoiding the wake-up of the virtual machine, which allows for hot plugging or hot unplugging without consuming excessive resources or creating unnecessary network traffic.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If interrupts are transmitted immediately to virtual machines during hot plugging or hot unplugging, then device management operations can be performed, but virtual machines wake up unnecessarily consuming significant computing resources and generating unnecessary network traffic

Engineering Contradiction:

Improvedevice management efficiencyVSAvoidcomputing resource consumption

Core Design Contradiction:

ProductivityVSUse of energy by moving object

Solution Approach 1:

The system performs preliminary actions by checking whether a virtual machine is in an idle state before transmitting an interrupt. This preliminary check prevents unnecessary wake-ups and resource consumption while still allowing device management operations to proceed when needed.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system introduces an intermediary mechanism (the interrupt transmission control logic) that mediates between the interrupt generation and the virtual machine. This intermediary checks the virtual machine's state and decides whether to transmit the interrupt, thereby preventing direct unnecessary wake-ups.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Productivity

If interrupts are transmitted immediately to virtual machines during hot plugging or hot unplugging, then device management operations can be performed, but unnecessary network traffic is generated

Engineering Contradiction:

Improvedevice management efficiencyVSAvoidnetwork traffic

Core Design Contradiction:

ProductivityVSLoss of substance

Solution Approach 1:

The system performs preliminary actions by checking whether a virtual machine is in an idle state before transmitting an interrupt. This preliminary check prevents unnecessary wake-ups and resource consumption while still allowing device management operations to proceed when needed.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system introduces an intermediary mechanism (the interrupt transmission control logic) that mediates between the interrupt generation and the virtual machine. This intermediary checks the virtual machine's state and decides whether to transmit the interrupt, thereby preventing direct unnecessary wake-ups.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Use of energy by moving object

If virtual machines are kept in idle state to save resources, then computing resource consumption is reduced, but device hot plugging or hot unplugging cannot be performed

Engineering Contradiction:

Improvecomputing resource consumptionVSAvoiddevice management capability

Core Design Contradiction:

Use of energy by moving objectVSAdaptability or versatility

Solution Approach 1:

The system dynamically adjusts interrupt transmission based on the virtual machine's state. When a virtual machine is in an idle state, interrupts are delayed until it transitions to an awake state. When the virtual machine is already awake or transitions to awake state, interrupts are transmitted to enable device management operations.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system performs preliminary actions by checking whether a virtual machine is in an idle state before transmitting an interrupt. This preliminary check prevents unnecessary wake-ups and resource consumption while still allowing device management operations to proceed when needed.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS20240086220A1Delaying interrupts for virtual machines

Publication Date: 2024.03.14 RED HAT INC

AI summary

A computing device can detect an interrupt associated with a virtual machine. Based on detecting the interrupt, the computing device can determine whether the virtual machine is in an idle state. Based on determining that the virtual machine is in the idle state, the computing device can delay the interrupt by storing the interrupt in an interrupt register for a period of time and preventing the interrupt from being transmitted to the virtual machine during the period of time. After storing the interrupt in the interrupt register, the computing device can determine that the virtual machine is in an awake state. In response to determining that the virtual machine is in the awake state, the computing device can transmit the interrupt from the interrupt register to the virtual machine.