On Freitag, 28. Juni 2019 16:23:08 CEST Greg Kurz wrote: > > > This feature applies to all backends IIUC. We don't really care for the > > > synth backend since it generates non-colliding inode numbers by design, > > > but the proxy backend has the same issue as local. So... > > > > Yeah, I was not sure about these, because I did not even know what these > > two were for exactly. :) [ lazyness disclaimer end] > > "proxy" is a backend where all I/O accesses are performed by a separate > process running the virtfs-proxy-helper command. It runs with root > privileges, which provides the same level of functionality as "local" > with security_model=passthrough. It also chroot() into the shared > folder for extra security. But it is slower since it all requests > still go through the virtio-9p device in QEMU. This would call > for a vhost-9p implementation, but it's yet another story. > > "synth" is a software pseudo-backend, currently used to test 9pfs > with QTest (see tests/virtio-9p-test.c).
Thanks for the clarification! So the proxy backend sounds like an idea that has not been implemented fully to its end. I guess it is not really used in production environments, right? What is the actual motivation for this proxy backend? And now that I look at it, I am a bit surprised that there is this pure Unix pipe socket based proxy variant, but no TCPIP network socket variant. I mean the latter is AFAIK the original idea behind the 9p protocol and IMO might be interesting to physical separate pure storage backends that way. Best regards, Christian Schoenebeck