See this PR for more info: https://github.com/tokio-rs/tokio/pull/3756
As a workaround use a pair of connected unix sockets - this obviously
incurs some overhead, albeit not measureable on my machine. Once tokio
includes the fix we can go back to a DuplexStream for performance and
simplicity.
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>