Microsoft At the ongoing Microsoft Build 2019 conference, an updated WSL2 (Windows Subsystem for Linux) subsystem was announced, designed to run Linux executable files on Windows. The key feature of the second edition is the provision of a full Linux kernel, instead of a layer that dynamically translates Linux system calls into Windows system calls.
A test release of WSL2 will be available at the end of June in experimental builds. Support for WSL1, based on an emulator, will be maintained, and users will be able to use it alongside WSL2. A lightweight virtual machine, already used in Azure, is utilized to launch the Linux kernel in the Windows environment.
WSL2 for Windows 10 will include a component with the native Linux kernel 4.19. As fixes for the LTS branch 4.19 are released, the kernel for WSL2 will be promptly updated through the Windows Update mechanism and tested in Microsoft's continuous integration infrastructure. WSL2 will use the same kernel that is deployed in Azure infrastructure, simplifying maintenance.
All changes prepared for kernel integration with WSL will be published under the free GPLv2 license and will be contributed upstream. The prepared patches include optimizations to reduce kernel boot time, decrease memory consumption, and retain only the minimal necessary set of drivers and subsystems in the kernel. The proposed kernel will be able to transparently replace the emulation layer provided in WSL1. Access to the source code will allow enthusiasts to create their own Linux kernel builds for WSL2, for which necessary instructions will be prepared.
Using the native kernel with optimizations from the Azure project will achieve full compatibility with Linux at the system call level and enable seamless execution of Docker containers in Windows, as well as support for file systems based on the FUSE mechanism. Moreover, WSL2 significantly increases input/output performance and file system operations, which were previously bottlenecks in WSL1. For example, when unpacking a compressed archive, WSL2 is 20 times faster than WSL1, and for operations
like 'git clone', 'npm install', 'apt update', and 'apt upgrade', it is 2-5 times faster.
Despite the supply of the Linux kernel, WSL2 will not provide a ready-made set of user space components as before. These components are installed separately and are based on builds from various distributions. For example, to install in WSL from the Microsoft Store Debian GNU/Linux, Kali Linux , , and . To interact with the Linux kernel provided in Windows, a small initialization script must be injected into the distribution, modifying the boot process. Canonical has already expressed its intention to ensure full support for running Ubuntu on WSL2.
Additionally, it can be noted by Microsoft with a terminal emulator , the code of which is distributed under the MIT license. Along with the terminal, the code for the original command-line interface conhost.exe, used in Windows and implementing the Windows Console API, has also been opened. The terminal provides a tabbed interface and split windows, fully supports Unicode and escape sequences for colored output, allows theme changes, and supports extensions, virtual consoles (PTY), and uses DirectWrite/DirectX for text rendering acceleration. The terminal can use Command Prompt (cmd), PowerShell, and WSL shells. This summer, the new terminal will be available to Windows users through the Microsoft Store.
Source: opennet.ru
