Goferless Filesystem Available

[Ayush Ranjan]

Hi all,

We recently landed support for directfs feature in runsc. This is a filesystem optimization feature. It enables the sandbox to access the container filesystem directly (without having to go through the gofer). This should improve performance for filesystem heavy workloads.

You can enable this feature by adding `--directfs` flag to the runtime configuration. The runtime configuration is in `/etc/docker/daemon.json` if you are using Docker. This feature is also supported properly on k8s.

We are looking for early adopters of this feature. You can file bugs or send feedback using this link. We look forward to hearing from you!

NOTE: This is completely orthogonal to the "Root Filesystem Overlay Feature" introduced earlier. You can stack these optimizations together for max performance.

[Ayush Ranjan]

This feature has been made the default in runsc after https://github.com/google/gvisor/commit/6b317756e88456d58a4fd4c176b3ea4e6654096d.

If this change breaks you, please let us know via GitHub issues. To unbreak use --directfs=false.