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QNX Hypervisor User's Guide
This User's Guide explains the QNX hypervisor architecture and provides instructions for installing and running a QNX Hypervisor system, changing system components and configuration, and using hypervisor features such as virtual devices (vdevs).
Monitoring and Troubleshooting
This chapter describes some tools and techniques you can use to monitor and troubleshoot your hypervisor system.
Gathering information about a virtual machine
QNX Hypervisor provides ways for gathering information about the VM running inside of a qvm process.

QNX Momentics IDE User's Guide
This User's Guide describes version 8.0 of the Integrated Development Environment (IDE) that's part of the QNX Tool Suite.
QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running the QNX OS 8.0.
QNX Software in the Cloud
QNX Software in the Cloud enables developers to use the QNX OS in the Amazon cloud environment.
QNX Toolkit for Visual Studio Code
This User's Guide describes the QNX^® Toolkit for Visual Studio Code. The guide introduces you to the QNX Toolkit by explaining the QNX development environment and how to build, run, and debug your QNX^® Operating System (OS) applications and systems.
QNX Hypervisor User's Guide
This User's Guide explains the QNX hypervisor architecture and provides instructions for installing and running a QNX Hypervisor system, changing system components and configuration, and using hypervisor features such as virtual devices (vdevs).
- Understanding QNX Virtual Environments
  QNX hypervisors are designed to meet the expectations of a hypervisor specified by the Popek/Goldberg Theorem.
- QNX Hypervisor: Protection Features
  This chapter explains the main features used by the QNX Hypervisor to protect itself and its guests. Many of these features are part of the design, while others are configurable.
- Configuration
  A QNX hypervisor, its qvm processes that create the VMs in which guests run, and these guests must be configured to work together.
- Building a QNX Hypervisor System
  This chapter explains how to build (assemble) a QNX Hypervisor system and transfer a bootable image to a supported target platform.
- Booting and Shutting Down
  This chapter describes how to boot and shut down the hypervisor host and guests in a QNX hypervisor system.
- Using Virtual Devices, Networking, and Memory Sharing
  This chapter describes how guests can discover and connect to vdevs and how they can use important hypervisor capabilities, such as networking and memory sharing.
- Monitoring and Troubleshooting
  This chapter describes some tools and techniques you can use to monitor and troubleshoot your hypervisor system.
  - Troubleshooting strategies
    There are numerous ways to get information about the different parts of your hypervisor system.
  - Viewing hypervisor activity
    After the hypervisor guest has booted, you can use QNX Momentics IDE to open a command terminal to either the host or a guest and then view its resource usage and activity.
  - Getting hypervisor trace information
    You can use the tracelogger utility and the QNX Momentics IDE System Profiler to capture and examine trace events from a VM.
  - Gathering information about a virtual machine
    QNX Hypervisor provides ways for gathering information about the VM running inside of a qvm process.
  - OS-VM configuration mismatch
    A guest may fail to start or not perform as expected if the VM in which it is running is not configured with the vdevs the guest OS expects to find.
  - Getting a guest dump during a crash
    You can configure your guest and the watchdog vdev in its VM to dump the guest's state in the event of a crash.
  - qvm process exit codes
    When a qvm process exits, the shell exit status indicates the reason for the exit.
- Performance Tuning
  This chapter describes common sources of overhead in a QNX hypervisor system, and strategies for reducing this overhead and optimizing system performance.
- VM Configuration Reference
  When you specify options to configure a qvm process, you are assembling and configuring the components of a virtual machine (VM) in which a guest will run.
- Virtual Device Reference
  This chapter presents the virtual devices (vdevs) delivered with QNX hypervisors, and describes how to configure these vdevs.
- Virtual Machine Firmware
  The virtual machines (VMs) in a QNX Hypervisor system provide a comprehensive firmware interface for guest OSs to manage VM power settings, access timers, and more.
- Utilities and Drivers Reference
  This chapter describes the utilities and drivers delivered with the QNX hypervisor.
- Terminology
  The following terms are used throughout the QNX hypervisor documentation.
Typographical Conventions, Support, and Licensing
This section describes the typographical conventions used throughout the documentation, explains how to obtain technical support, and provides some information about licensing.

Gathering information about a virtual machine

QNX Hypervisor provides ways for gathering information about the VM running inside of a qvm process.

This runtime VM information is useful for systems integrators and anyone setting up guest OSs and drivers. Here we only summarize the mechanisms for getting this information. For details about the specific data that each mechanism provides, go to the corresponding note in the QNX Hypervisor GitLab Repository at: https://gitlab.com/qnx/hypervisor/tools-for-qnx-hypervisor/gathering-information-about-a-virtual-machine.

Getting guest status (SIGUSR1) and guest dumps (SIGUSR2)

You can send the SIGUSR1 signal to a qvm process to obtain human-readable (i.e., text-based) information about the VM, as follows:

slay -sSIGUSR1 qvm

This signal causes qvm and all loaded vdevs to log free-form text describing their current status at the QL_QVM_INFO level (i.e., information type messages). For an explanation of filtering messages by their type and specifying the logging destination for a VM, refer to the logger option description.

The information logged includes runtime data from vdevs and other sources, and is useful for troubleshooting guest OS and driver behavior.

Alternatively, you can send the SIGUSR2 signal to a qvm process to dump the hosted guest's state— meaning its memory and CPU registers—and other troubleshooting-related information at any time. (The guest continues running after the dump.) For information on specifying the file that the dump is written to and on its contents, go to the dump option reference.

Reading VM runtime information from the env file

Each qvm process creates a file that provides details about the VM. This file is kept at /dev/qvm/name/env on the host, where name is the system name for the guest. This system name is set via the system option in the qvm configuration. For example, if your hypervisor system has a guest called linux1, the underlying qvm process produces a file called /dev/qvm/linux1/env.

This file is in JSON format, so it is machine- and human-readable, and it provides information that can't be known before qvm starts, such as vCPU thread IDs and architecture-specific errata data. The exact errata reported are controlled by configuration variable settings; for details, refer to the Configuration variables section.

Page updated: August 11, 2025