The Evolution of the Nydus Image Acceleration
The Evolution of the Nydus Image Acceleration
Optimized container images together with technologies such as P2P networks can effectively speed up the process of container deployment and startup. In order to achieve this, we developed the Nydus image acceleration service (also a sub-project of CNCF Dragonfly).
In addition to startup speed, core features such as image layering, lazy pulling etc. are also particularly important in the field of container images. But since there is no native filesystem supporting that, most opt for the userspace solution, and Nydus initially did the same. However user-mode solutions are encountering more and more challenges nowadays, such as a huge gap in performance compared with native filesystems, and noticable resource overhead in high-density employed scenarios.
Therefore, we designed and implemented the RAFS v6 format which is compatible with the in-kernel EROFS filesystem, hoping to form a content-addressable in-kernel filesystem for container images. After the lazy-pulling technology of "EROFS over Fscache" was merged into 5.19 kernel, the next-generation architecture of Nydus is gradually becoming clear. This is the first native in-kernel solution for container images, promoting a high-density, high-performance and high-availability solution for container images.
This article will introduce the evolution of Nydus from three perspectives: Nydus architecture outline, RAFS v6 image format and "EROFS over Fscache" on-demand loading technology.
Please refer to Nydus for more details of this project. Now you can experience all these new features with this user guide.