This page describes how to count and trace performance events in the KVM kernel module. There are two tools, kvm_stat and kvm_trace, which were previously used for these tasks. Now this can be done using standard Linux tracing tools. Contents [hide] 1 Counting events 2 Tracing events 3 Recording events 3.1 Recording events for a guest 3.1.1 Using copies of guest files 3.1.2 Using… Continue reading how to count and trace performance events in the KVM kernel module
Author: technology
How KVM deals with memory
This was written in February 2010, during the era of qemu-kvm 0.12. The qemu/kvm process runs mostly like a normal Linux program. It allocates its memory with normal malloc() or mmap() calls. If a guest is going to have 1GB of physical memory, qemu/kvm will effectively do a malloc(1<<30), allocating 1GB of host virtual space.… Continue reading How KVM deals with memory
KVM File layout in kernel
The first kvm releases its file in the directory drivers/kvm/, but since around December 2007 it is pushed into virt/kvm directory in the kernel source tree. Other files are also listed here. Contents [hide] 1 Architecture independent files of kvm 1.1 virt/kvm 2 Architecture dependent files 2.1 arch/x86/kvm 2.2 include/linux 2.3 include/asm-x86/ Architecture independent files of kvm virt/kvm ioapic.h ioapic.c iodev.h… Continue reading KVM File layout in kernel
Linux KVM
Kernel Virtual Machine KVM (for Kernel-based Virtual Machine) is a full virtualization solution for Linux on x86 hardware containing virtualization extensions (Intel VT or AMD-V). It consists of a loadable kernel module, kvm.ko, that provides the core virtualization infrastructure and a processor specific module, kvm-intel.ko or kvm-amd.ko. Using KVM, one can run multiple virtual machines… Continue reading Linux KVM
Harmonyos Configuration File Elements
This section describes all attributes in the application configuration file config.json. DevEco Studio offers two views for you to edit the config.json file, namely, Code and Visualized. You can change the view in the upper right corner of the config.json editing window.Figure 1 Visualized view for editing the config.json file Internal Structure of the Configuration File The config.json file consists of three mandatory tags, namely, app, deviceConfig, and module.… Continue reading Harmonyos Configuration File Elements
Harmonyos Configuration File Composition
The root directory for each HAP file of an application contains a config.json file, which provides the following information: Global configuration information of the application, including the basic information about the application, such as the bundle name, version number, and vendor Device-specific configuration information of the application, including the backup and restoration as well as network security… Continue reading Harmonyos Configuration File Composition
Harmonyos Application Fundamentals
User Applications A user application, also known as an application or app, runs on the operating system of devices and provides particular services for users. Applications running on HarmonyOS are classified into the following forms: Applications installed in a conventional manner Installation-free applications (namely, Atomic Services) that provide specific functions Unless otherwise specified, applications in HarmonyOS documentation refer to the… Continue reading Harmonyos Application Fundamentals
Harmonyos System Security
HarmonyOS-powered distributed devices ensure that the right person uses the right data through the right device. Ensure the right person by performing distributed collaborative identity authentication. Ensure the right device by building a trusted operating environment on the distributed device. Ensure the right data by implementing classified and hierarchical management of data transmitted across devices. Right… Continue reading Harmonyos System Security
Harmonyos Technical Features
Hardware Collaboration and Resource Sharing The key features for hardware collaboration and resource sharing include DSoftBus, Distributed Device Virtualization, Distributed Data Management, and Distributed Scheduler. DSoftBus DSoftBus is a communication base for interconnecting devices, such as mobile phones, tablets, wearables, smart TVs, and head units. It powers devices with distributed communication capabilities, allowing for auto discovery and zero-wait transmission… Continue reading Harmonyos Technical Features
About HarmonyOS
System Positioning HarmonyOS is an innovative, distributed operating system for a fully-connected world. Unlike a legacy operating system that runs on a standalone device, HarmonyOS is built with a distributed architecture that uses a same set of system capabilities to adapt to a wide array of device forms, ranging from phones and tablets to wearables, smart TVs, and… Continue reading About HarmonyOS