Vhost vs virtio. The Virtio input device is a paravirtualized device for input events. During this process, you’ll learn how to serve different content to different visitors depending on which domains they are requesting by creating two virtual host sites. Jan 19, 2021 · Each virtio-blk device appears as a disk inside the guest. Today's high-end servers have more processors, and guests running on them often have an increasing number From Convenience to Performant VirtIO Communication Amery Hung, Linux Kernel Engineer Bobby Eshleman, Linux Kernel Engineer Systems Technology and Engineering, ByteDance Jun 9, 2022 · SCMI Vhost and Virtio backend implementation This RFC series, provides ARM System Control and Management Interface (SCMI) protocol backend implementation for Virtio transport. Interfaces: QEMU further categorizes virtio-gpu device variants based on the interface exposed to the guest. A detailed view of the vhost user protocol and its implementation in OVS DPDK, qemu and virtio-net Jan 3, 2021 · Also in case of vhost-net, hw/net/virtio-net. The guest can send commands, data, and requests. - VIRTIO_SCMI_F_P2A_CHANNELS feature is not negotiated, as notifications and delayed response are not implemented at present. This allows virtiofsd to run as a separate process from QEMU and with its own sandboxing. 2. 1. Multi-Queue virtio-net Copy link Multi-queue virtio-net provides an approach that scales the network performance as the number of vCPUs increases, by allowing them to transfer packets through more than one virtqueue pair at a time. This is good from the security perspective, especially if you want use virgl 3D acceleration, and it also helps with opengl performance. Contribute to expressjs/vhost development by creating an account on GitHub. The main advantage is the unified software stack for all vDPA devices: vhost Vhost-user Protocol Table of Contents Vhost-user Protocol Introduction Support for platforms other than Linux Message Specification Header Payload A single 64-bit integer A vring state description A vring descriptor index for split virtqueues Vring descriptor indices for packed virtqueues A vring address description Memory region description Single memory region description Multiple Memory Feb 15, 2021 · 纵观virtio网络的发展， 控制平面由最原始的virtio到vhost-net协议，再到vhost-user协议，逐步得到了完善与扩充; 数据平面上，从原先集成在QEMU中或内核模块的中，到集成了DPDK数据平面优化技术的vhost-user，最终到使用硬件加速数据平面。 在保留virtio这种标准接口的前提下，达到了SR-IOV设备直通的网络 Supported Guest Operating Systems The guest OS must contain virtio-scsi or virtio-blk drivers. vhost-scsi: nvme0n1 1x virtio-scsi controller with 1x LUN: 235k IOPs @ 145 usec 4x virtio-scsi controller with 4x LUN: 715K IOPs @ 185 usec KVM guest configuration Both virtio-blk + virtio-scsi using single virtio queue Virtio-scsi enabled with scsi_mod. c ?? Oct 11, 2016 · Future tasks Pick up vhost-scsi work again: Port QEMU hw/virtio-scsi. KVM Virtual storage provisioning is to expose host persistent storage to guest for applications’ use. 4. The primary types are name-based virtual hosting, IP-based virtual hosting, and port-based virtual hosting. When you're managing multiple websites on a single Linux server, Apache2’s Virtual Hosts (vHOSTS) system is what allows you to serve different websites based on the domain name a user enters. Overview A vDPA device means a type of device whose datapath complies with the virtio specification, but whose control path is vendor specific. Below is a list of documentation pages which explain all details of virtual host support in Apache HTTP Server: Apache2 is a versatile, open-source web server supporting virtual hosting, SSL/TLS, and modular features, ideal for hosting multiple secure websites. Windows virtio drivers must be installed separately. There is a vhost-user backend that runs the graphics stack in a separate process for improved isolation. vhost-user virtio gpu There is a vhost-user variant for both virtio vga and virtio gpu. Sep 26, 2019 · Prior posts / Resources Introducing virtio-networking: Combining virtualization and networking for modern IT Introduction to virtio-networking and vhost-net Deep dive into Virtio-networking and vhost-net Hands on vhost-net: Do. This turns vhost-user into a VIRTIO transport and vhost-user devices become full VIRTIO devices. Sep 20, 2019 · For an application running on the user space to consume the virtio-pmd it needs to be linked with the DPDK library as well. Vhost is a kernel acceleration I just read an article on this. The draft specification has all interested parties aligned and is maturing quickly. Figure 5. Name-based virtual hosting uses the host name presented by the client. VSOCK VM Sockets (vsock) is a fast and efficient guest-host communication mechanism. The interfaces vhost-user back ends vhost-user back ends are way to service the request of VirtIO devices outside of QEMU itself. Sep 9, 2019 · The vhost-net/virtio-net based architecture described in this post is the first in a number of virtio-networking architectures which will be presented in a series of posts which differ by their performance, application ease of usage and actual deployments. - VIRTIO_SCMI_F_SHARED_MEMORY feature is not negotiated. With only Virtio involved, it's always the QEMU process that handles all I/O traffic. Jun 25, 2024 · While VirtIO presents a larger attack surface within the virtualization layer (between the guest OS and host kernel/virtual switch) that can potentially compromise the security of the service OS QEMU VIRTIO-IOMMU Device Dynamic instantiation in ARM virt (dt mode) VIRTIO, VHOST, VFIO, DPDK use cases Sep 15, 2023 · vsock 36864 2 vmw_vsock_virtio_transport_common,vhost_vsock vhost 49152 2 vhost_vsock,vhost_net vhost virtio-vsock is a vhost-based virtio device. Whether you are setting up a local testing server or managing a production server, knowing how to configure Virtual Hosts is an essential skill. Aug 13, 2025 · We’ll then dive into both kernel-based vhost and vhost-user architectures, examining each in detail—including their advantages, drawbacks, typical use cases, and how they affect performance. Apache server installed. The SCMI Vhost driver adds a misc device (/dev/vhost-scmi) that exposes the SCMI Virtio channel capabilities to userspace: - Set up cmdq, eventq. Sep 18, 2019 · Vhost-net has silently become the default traffic offloading mechanism for qemu-kvm based virtual environments leveraging the standard virtio networking interface. It bears a resemblance to a display server protocol, if you consider QEMU as the display server and the back-end as the client, but in a very limited way. This reduces copy operations, lowers latency and CPU usage. Virtio-net is slower, but newer and more stable or compatible. virtio-blk was available before virtio-scsi and is the most widely deployed virtio storage controller. It is intended for architects and developers who are interested in understanding the nuts and bolts of this architecture, and will be followed by a complementary hands on blog to explore Sep 27, 2019 · This device can be placed in a PCI Express slot. In this post we will cover the use cases for those two bus drivers and how they can be put to use for bare metal, container and VM. Jan 21, 2024 · Understanding Apache Virtual Hosts is crucial for anyone managing a web server. After we have explained the scenario in the previous post, we are reaching the main point: how does the data travel from the virtio-device to the driver and back? virtio在虚拟机中，可以通过qemu模拟e1000网卡，这样的经典网卡一般各种客户操作系统都会提供inbox驱动，所以从兼容性上来看，使用类似e1000的模拟网卡是非常一个不错的选择。 但是，e1000网卡上也包含了复杂的io… Aug 14, 2011 · Overview Discuss a range of topics about KVM performance How to improve out of the box experience Jun 29, 2021 · virtio-vga与virtio-gpu是qemu模拟的较新的显卡设备，它们都是由Dave Airlie等人引入，避免通过直通GPU来加速虚拟机内部的3D渲染。x86下使用virtio-vga，arm下使用virtio-gpu，guest里使用virtio-gpu作为前端驱动。x86下如果Guest OS中没有virtio-gpu驱动，则使用兼容的标准vga模式。此外为了提供高性能，virtio-vga与virtio-gpu * any extra features being enabled, such as TSO and mrg-Rx. vhost IOMMU is a feature which restricts the vhost memory that a virtio device can access, and as such is useful in deployments in which security is a concern. The interface is defined to be easy to use and implement. vhost vhost技术对virtio-net进行了优化，在内核中加入了vhost-net. g. 04 server. Currently it used in KubeVirt by libvirt and qemu to communicate with the qemu-guest-agent. e. vDPA devices can be both physically located on the hardware or emulated by software. The guest kernel will probe the vhost-vsock pci device and load its driver. This mechanism allows the network processing to be performed in a kernel module freeing the qemu process and improving the overall network performance. The purpose of this feature is to provide para-virtualized interfaces to guest VMs, to various If there's no dependency (i. Dec 16, 2024 · Virtual hosting is categorized into different types based on how multiple websites or services are hosted on a single server. The purpose of this feature is to provide para-virtualized interfaces to guest VMs, to various hardware blocks like clocks, regulators. This virtual host is useful when one wants to host multiple projects for businesses managing multiple domains with a single server. In the Data Plane Development Kit (DPDK), we provide a virtio Poll Mode Driver (PMD) as a software solution, comparing to SRIOV hardware solution, for fast guest VM to guest VM communication and guest VM to host communication. There is no try How vhost-user came into being: Virtio-networking and DPDK A journey to the vhost-users realm vhost-vsock architecture Uses vhost driver framework to integrate with host network stack Both guest and host applications use sockets API Socket types: SOCK_STREAM (connection-oriented, reliable, ordered) SOCK_DGRAM (connectionless, unreliable, unordered) Agent Network stack Client app virtio_transport Jun 9, 2022 · Add Vhost implementation for SCMI over Virtio transport. use_blk_mq=1 Explicit IRQ affinity of virtioX-request MSI-X vectors Oct 10, 2024 · In QEMU 9. A small vDPA parent driver in the host kernel is required only for the control path. Originally developed as a standard for paravirtualized devices implemented by a hypervisor, it can be used to interface any compliant device (real or emulated) with a driver. Vhosts allow several websites to share resources from a physical server. To do this there are a number of things required. IOMMU support may be enabled via a global config value, vhost-iommu-support. The code is mostly boilerplate although each device has a chardev option which specifies the ID of the --chardev device that Ring buffers provide a simple and efficient mechanism for guest-host communication Sep 22, 2023 · Therefore, within the framework of the vhost-user technology, the developers proposed a new approach: moving the data plane of VirtIO devices into a separate user space process. virtio-net VHOST_USER_SEND_RARP) Jul 25, 2022 · The driver of the guest kernel talks with the virtio-net device using memory mapped I/O (MMIO) and interrupts, like for a real hardware device. cmdq Figure 5. VirtIO Transports VirtIO supports a number of different transports. You can see more information in previous blogs, like vhost-net deep dive or the journey to vhost-user. This diagram gives a high-level overview: An irqfd is a mechanism for injecting a specific interrupt into the guest VM using an eventfd. ko模块，使得对网络数据可以在内核态得到处理。 图中描述了vhost的io路径: guest发出中断信号退出kvm，kvm直接和vhost-net. h> Python - starting from Python 3. Jul 23, 2025 · Setting up a virtual host in Apache web server on Linux allows us to host multiple websites on a single server. VIRTIO_F_IOMMU_PLATFORM, if this feature bit is provided in the device, then the guest virtio driver is forced to use dma api to manage all corresponding dma memory access, otherwise the device will be disabled by system compulsorily. The virtio_vsock driver initializes the emulated vhost-vsock device. , libblkio) through the vhost-vdpa bus. This virtio driver is registered in ‘virtio_vsock_init’ function. In virt-manager, I created a VirtIO Jun 21, 2023 · In this blog we will discuss VirtIO and GPU virtualisation challenges along with the progress the Linaro development teams are making in this space. When mixing writes with reads (25 %, 50 %), virtio-scsi is either the leader or in the worst case within few % of virtio-blk. load the vhost_vsock driver in host. This saves IP addresses and the associated administrative overhead but the protocol being served must supply the host name at an appropriate point. virtual domain hosting. The virtual device, virtio-user, with unmodified vhost-user backend, is designed for high performance user space container networking or inter-process communication (IPC). Feb 27, 2021 · vhost 是 virtio 的一种后端实现方案， 在 virtio 简介中，我们已经提到 virtio 是一种半虚拟化的实现方案，需要虚拟机端和主机端都提供驱动才能完成通信，通常，virtio 主机端的驱动是实现在用户空间的 qemu 中，而 vhost 是实现在内核中，是内核的一个模块 vhost-net. Before you begin this tutorial, you will need: Versions 1. Virtio on Linux ¶ Introduction ¶ Virtio is an open standard that defines a protocol for communication between drivers and devices of different types, see Chapter 5 ("Device Types") of the virtio spec ([1]). For a high level introduction of what is virtio technology refer to the introduction blog. Here is a complete index of all the posts that comprise the blog series. Sep 3, 2020 · In part 2 of the vDPA kernel framework series, we discussed the design and implementation of vhost-vDPA bus driver and virtio-vDPA bus driver. ko。为什么要实现在内核中，有什么 62. As was discussed in a previous blog, virtio-blk added the iothread-vq-mapping feature to allow users to create multiple iothreads and map them to different virtqueues. The simple answer is that VirtIO-SCSI is slightly more complex than VirtIO-Block. IP-address-based vhosts assign a different IP address to a website, and name-based vhosts assign multiple hostnames to a single IP address. Creating virtual host configurations on your Apache server does not magically cause DNS entries to be created for those host names. > > > > > > - virtio_scsi_common_unrealize (dev); > > > vhost_user_cleanup (&s->vhost_user); > > > + virtio_scsi_common_unrealize (dev); > > > } > > > > > > static Property vhost_user_scsi_properties [] = { > > > diff --git a May 4, 2021 · In other words, just like vhost-user but able to emulate NVMe devices instead of virtio-blk or virtio-scsi devices. Existing VIRTIO device emulation code can then be reused in vhost-user device backends. This can be done entirely in QEMU, divided between QEMU and the kernel (vhost) or handled by a separate process which is configured by QEMU (vhost-user). vhost-user device These are simple stub devices that ensure the VirtIO device is visible to the guest. by SR-IOV device PT Faster simple forwarding by ‘cache’ Remains historical gaps of cloudlization Sep 27, 2020 · Conclusion The vhost-user protocol can be simplified by adopting the vhost vDPA ioctls that have recently been introduced in Linux. NFS -- IDE vs SATA vs VirtIO vs Virtio SCSI I noticed while running the test, that when CrystalDiskMark took a really long time to create the test file compared to CIFS/SMB. Mar 28, 2021 · 本文探讨了Linux虚拟化中的Virtio框架，比较了Vhost与Vhost-user技术，重点讲解了它们如何优化I/O性能，包括Virtio的基本原理、vhost对网络数据处理的改进以及vhost-user的用户空间处理方式。 Jul 11, 2021 · vhost protocol - A protocol that allows the virtio dataplane implementation to be offloaded to another element (user process or kernel module) in order to enhance performance. Feb 21, 2024 · In the case of virtio-net devices, the guest sees a Virtio device, so it can only interact with it using Virtio. c and hw/virtio/virtio-net-pci. Virtio uses a "transport," usually PCI, to communicate with the guest. Jan 12, 2021 · Both settings use the same "virtio-net-pci" device as "virtio-net" is only an alias: The only difference is that the slower "virtio-net" setting removes the "vhost=on" flag (open the VM logs to see this setting): virtio-net. The SPDK vhost target has been tested with recent versions of Ubuntu, Fedora, and Windows QEMU Userspace vhost-scsi target support was added to upstream QEMU in v2. Vhosts can be IP-address-based or name-based. Formalization in Virtio Specification Codes in qemu userspace virtio-net backend Vhost protocol extension: Vhost-kernel (uapi), vhost-user (has its own spec) Versions, feature negotiations, compatibility Vhost support codes in qemu (user and kernel) Features (bugs) duplicated everywhere: vhost_net, dpdk, TAP, macvtap, OVS, VPP, qemu Aug 12, 2020 · The userspace vhost drivers or kernel virtio drivers control and setup the hardware datapath via vhost ioctls or virtio bus commands (depending on the subsystem you chose). Apr 18, 2022 · In this guide, you will set up Apache virtual hosts on an Ubuntu 20. Virtual Hosts allow you to run multiple websites on a single server. Aug 10, 2022 · Table of Contents 基础知识 QEMU & KVM IPC 方式 Virtio Networking Virtio Virtio spec Virtio-net vhost-net References 这个文章主要 Feb 12, 2024 · Containers, VMs, or bare-metal As mentioned in the introduction, vDPA supports different buses such as vhost-vdpa and virtio-vdpa. git code Update vhost-scsi to implement latest virtio-scsi device specification Ensure vhost-scsi I/O still works Design libvirt 5. As IO depth increases, virtio-scsi takes the lead. 0. Both drivers are based on the vDPA bus which is explained in part 1 of the vDPA kernel framework series. Sep 9, 2019 · The vhost-net/virtio-net based architecture described in this post is the first in a number of virtio-networking architectures which will be presented in a series of posts which differ by their performance, application ease of usage and actual deployments. This diagram shows how this all comes together: If we compare this architecture to the kernel based vhost-net/virtio-net architecture the vhost-net was replaced with vhost-user while virtio-net was replaced with virtio-pmd. Sep 12, 2019 · By the end of this post, you’ll be able to understand how the vhost-net/virtio-net architecture works, the purpose of each of its components and how packets are sent and received. Compatibility with vhost-net and vhost-user virtio-mem is compatible with vhost-net. The vDPA framework will then forward the virtio/vhost commands to the hardware vDPA drivers which will implement those commands in a vendor specific way. It uses the same virtqueue layout as Virtio to allow Vhost devices to be mapped directly to Virtio devices. Sep 5, 2019 · Up until now we have covered virtio-networking and its usage in VMs. . this is not fixing a bug, \ just a stylistic improvement) it can stay in the same change. Implementation: Guest Guest Boot guest with a vIOMMU assigned. This allows the guest VMs to VIRTIO Native I/O Perf. c vhost-scsi support onto latest code add QEMU Object Model (QOM) support to the vhost-scsi device Port LIO vhost-scsi code onto latest lio. Storage Services Block Device Abstraction (BDEV) Qos 3rd Party Logical snapshots GPT DPDK Volumes clones Encryption Linux Ceph PMDK Virtio Virtio iSCSI NVMe AIO RBD blk SCSI Blk initiator BlobFS Blobstore RocksDB Virtio is a virtualization standard for network and disk device drivers where just the guest's device driver "knows" it is running in a virtual environment, and cooperates with the hypervisor. The virtio-blk device offers high performance thanks to a thin software stack and is therefore a good choice when performance is a priority. Most Linux and FreeBSD distributions include virtio drivers. Introduction The vhost-user-gpu protocol is aiming at sharing the rendering result of a virtio-gpu, done from a vhost-user back-end process to a vhost-user front-end process (such as QEMU). Since it is a separate process, it is not limited to the threading model that is traditionally used in QEMU and vhost (QEMU allocates a separate thread for every device). Borrowing the simple description from here: VirtIO Block has the following layers: guest: app -> Block Layer -> virtio-blk host: QEMU -> Block Layer -> Block Device Driver -> Hardware Whereas VirtIO SCSI has looks like this: guest: app -> Block Layer -> SCSI Layer -> scsi_mod host: QEMU -> Block Layer -> SCSI However, there are times (e. , boot, reboot, guest not using the vIOMMU), when the vIOMMU isn't active - all VM memory (including all plugged virtio-mem memory) has to be mapped by vfio. 2、Virtio 与 Vhost 协议介绍 Virtio 目前被用作虚拟机（VM）访问块设备（virtio-blk）和网络设备（virtio-net）的标准开放接口。 Virtio-net 作为一种虚拟网卡，是 virtio 迄今为止支持的最复杂的设备。 Part I：Virtio 是如何被构建出来的？ Apr 23, 2019 · We show how to set up vhost targets as a local SPDK storage service and measure the basic set of performance numbers in comparison to local NVMe-over-fabrics connections. QEMU vhost-user-input - Input emulation This document describes the setup and usage of the Virtio input device. 1 and later of Apache support both IP-based and name-based virtual hosts (vhosts). Run the following Vhost-user与vhost的区别 Vhost是client与kernel（server）的交互，client与内核共享内存，局限性是如果client要发送消息到用户进程，很不方便； Vhost-user使用unix domain来进行通信，两个用户进程共享内存，达到和vhost一样的效果。 Virtio-blk与virtio-scsi 他们都是在 virtio spec 里面定义的两种块设备实现。区别是 Para virtualization: virtio-blk, virtio-scsi Virtio ring buffer provides efficient transport for guest-host communication Provide more virtualization friendly interface, higher performance Device assignment Pass hardware to guest, high-end usage, high performance Exclusive access, limited number of slot in a server, hard to do live migration 虚拟机Guest-Host通信机制系列：vsock，virtio-vsock，upcall之间的关系 背景 VM socket（简称vsock）是一种虚拟套接字，用于在不同虚拟机或虚拟机和宿主机之间提供高性能、可靠的通信。 vsock内核模块的设计原理如下： 虚拟机与宿主机之间的通信通过一对虚拟套接字进行。 Jul 8, 2020 · This post continues where the "Virtio devices and drivers overview" leaves off. Moreover, as the guest driver is aware of its virtualized nature, the hypervisor can give it direct access to some host resources, like in the vhost interface (direct access to the networking Jun 9, 2022 · protocol backend implementation for Virtio transport. ko通信，然后由vhost-net. 7 Go - Matt Layher's vsock Jan 23, 2017 · When it comes to IOPS, randread in low IO depth case shows a slight drop for virtio-scsi without IO threads, but remains close throughout the other cases. Poll Mode Driver for Emulated Virtio NIC Virtio is a para-virtualization framework initiated by IBM, and supported by KVM hypervisor. This allows to run the virtio-gpu emulation in a separate process. Description The vhost-user-input device implementation was designed to work with a daemon polling on input devices and passes input events to the guest. Nov 18, 2019 · We also provided a comparison of the different virtio-networking architectures (vhost-net/virtio-net, vhost-user/virtio-pmd, virtio full HW offloading and vDPA). Virtio-serial can also be used by other agents, but it is a little bit cumbersome due to: A small set of ports on the virtio-serial Sync to video time Description Vhost-net/Virtio-net vs DPDK Vhost-user/Virtio-pmd Architecture 31Likes 3,537Views 2020Mar 5 The case is to measure vhost/virtio system forwarding throughput, and the theoretical system forwarding throughput is 100 Gbps. Both Vhost and Virtio is DPDK polling mode driver. Virtio is faster but may cause issues with certain setups (docker/VM issues). Sep 26, 2021 · 2. Background Right now KubeVirt uses virtio-serial for local guest-host communication. Additionally, it allows interaction with applications running directly on the host or within containers via the virtio Sep 24, 2019 · This post is a technical deep dive into the vhost-user/virtio-pmd architecture targeting high performance userland networking using DPDK, building on the introduction provided by the solution overview post. − Dedicated cores for vhost − Several devices shares a single vhost worker thread − Polling and optimization on interrupt − Dedicated I/O scheduler − Lack of cgroup support May 19, 2024 · 它通过将virtio设备的处理从虚拟机管理程序转移到用户态进程（如QEMU）或内核态进程（如vhost-net）中，以减少上下文切换和虚拟机管理程序的开销。 The virtiofs VIRTIO device is implemented in QEMU but the VM communicates directly with the vhost-user device backend in virtiofsd for most operations. Vhost is a protocol for devices accessible via inter-process communication. We started with the original vhost-net/virtio-net architecture, moved on to the vhost-user/virito-pmd architecture and continued to vDPA (vHost Data Path Acceleration) where the virtio ring layout was pushed all the way into the NIC providing wiresspeed/wirelatency to VMs. Apr 18, 2020 · When start qemu, we need add ‘-device vhost-vsock-pci,guest-cid= ' in qemu cmdline. Or do not. ko访问tap设备。 这样网络数据只需要经过从用户态到内核态的一次切换，就可以完成数据的传输 Sep 9, 2019 · The vhost-net/virtio-net based architecture described in this post is the first in a number of virtio-networking architectures which will be presented in a series of posts which differ by their performance, application ease of usage and actual deployments. c is not used at all as backend is now provided by host Kernel driver (vhost-net) and frontend is implement by hw/net/vhost_net. Standardization and support for vfio-user is currently underway in the QEMU community. The backend is the everything that QEMU needs to do to handle the emulation of the VirtIO device. You must have the names in DNS, resolving to your IP address, or nobody else will be able to see your web site. Jan 11, 2021 · Packages Fedora Copr repo Quickstart Host kernel requirements: CONFIG_VHOST_VSOCK=m Guest kernel requirements: CONFIG_VIRTIO_VSOCKETS=m Launch a guest and assign it CID 3: (host)# qemu-system-x86_64 -device vhost-vsock-pci,guest-cid=3 Language bindings C - use <linux/vm_sockets. The Breaking cloud native network performance barriers post moved on from the realm of VMs to the realm of containers. 0, this was fixed for virtio-blk and the Linux kernel vhost-scsi target. This means that the host kernel manages all the data transfer while the hypervisor is only responsible for dealing with control information. Virtio and vhost_net architectures vhost_net moves part of the Virtio driver from the user space into the kernel. For What is virtio-fs? Shares a host directory tree with the guest * Re: [PATCH] vhost: fix read vs write lock mismatch 2024-11-25 11:14 ` David Marchand 2024-11-25 16:28 ` David Marchand 0 siblings, 1 reply; 7+ messages in thread From: Maxime Coquelin @ 2024-11-25 16:20 UTC (permalink / raw) To: David Marchand, Stephen Hemminger; dev, stable, Chenbo Xia, Eelco Chaudron On 11/25/24 12:14, David Marchand wrote: > On Mon, Nov 18, 2024 at 5:24 PM Stephen vhost-user device is stopped and QEMU takes over vrings QEMU migrates VIRTIO device using common code vhost-user device is started again on destination Device-specific post-migration steps (e. The latter variant of virtual hosts is sometimes also called host-based or non-IP virtual hosts. May 24, 2022 · Unlike VirtIO drivers & devices, whose data plane exists in the Qemu process, VHost can offload the data plane to either another host user process (VHost-User) or to the host’s kernel (VHost, as a kernel module). 10. This flexibility enables the utilization of vDPA devices with virtual machines or user space drivers (e. There are two main types of virtual hosting, name-based and IP-based. Topic Solution Overview Deep Dive Hands On vhost-net Introduction to virtio-networking and vhost-net Deep dive into Virtio-networking Backends: QEMU provides a 2D virtio-gpu backend, and two accelerated backends: virglrenderer (‘gl’ device label) and rutabaga_gfx (‘rutabaga’ device label). Local NVMe-over-fabrics connections provide an alternative way to provide local storage service based on SPDK. 1. Aug 19, 2024 · After my previous experience of migrating IDE VM disks to VirtIO SCSI, I created a Win10 VM in virt-manager, with the primary disk being a SCSI disk from setup. yrdus iqru rsrr dumg myn qmwls fovob axwaiu mvpx pzhdk