Windows Insider builds with WSL2 subsystem (Windows Subsystem for Linux) published

Microsoft company announced on the formation of new experimental builds of Windows Insider (build 18917), which include the previously announced WSL2 (Windows Subsystem for Linux) layer, which ensures the launch of Linux executable files in Windows. The second edition of WSL is distinguished by the delivery of a full-fledged Linux kernel, instead of an emulator on the fly, translating Linux system calls into Windows system calls.

Using a standard kernel allows you to achieve full compatibility with Linux at the level of system calls and provide the ability to seamlessly run Docker containers on Windows, as well as implement support for file systems based on the FUSE mechanism. Compared to WSL1, WSL2 significantly improves I/O performance and file system operations. For example, when unpacking a compressed archive, WSL2 is 1 times faster than WSL20, and when performing “git clone”, “npm install”, “apt update” and “apt upgrade” operations, it is 2-5 times faster.

WSL2 offers a component based on the Linux 4.19 kernel that runs in a Windows environment using a virtual machine already in use in Azure. Updates for the Linux kernel are delivered through the Windows Update mechanism and tested on Microsoft's continuous integration infrastructure. All changes prepared for integrating the kernel with WSL are promised to be published under the free GPLv2 license. The prepared patches include optimizations to reduce kernel startup time, reduce memory consumption, and keep the minimum required set of drivers and subsystems in the kernel.

Support for the old version of WSL1 is retained and both systems can be used side by side, depending on user preference. WSL2 can act as a transparent replacement for WSL1. As in WSL1 userspace components Are established separately and are based on assemblies of various distributions. For example, to install in WSL in the Microsoft Store catalog offered assembly Ubuntu, Debian GNU/Linux, Kali Linux, Fedora,
Alpine, SUSE и openSUSE.

Environment performed in a separate disk image (VHD) with ext4 file system and virtual network adapter. Interfacing with the Linux kernel offered in WSL2 requires the distribution to include a small initialization script that changes the boot process. A new command "wsl --set-version" has been proposed to switch distribution modes, and to select the default WSL version, the command "wsl --set-default-version" has been proposed.

Source: opennet.ru