Re: [9fans] v9fs question

[Eric Van Hensbergen <ericvh@gmail.com>]

On Tue, Jul 14, 2009 at 2:05 PM, sqweek<sqweek@gmail.com> wrote:
>
>  I'm not too fond of the idea... It's not as though amount adds any
> new functionality over srv+mount[1], and I hate throwing more code at
> a problem when equivalent code exists elsewhere. Having to introduce a
> link time dependency on p9p doesn't help convince me either - the
> current arrangement seems to provide a decent seperation of
> responsibility.
>  The mount.9p symlink sounds pretty reasonable though, I'll get around
> to that sometime.
>
> [1] actually back when I read over amount I even concluded that it
> used the same trick as srv -a just with a pipe instead of unix socket!
> failed to notice the Tversion/Tattach subtlety. is it really worth the
> coupling to go back to that approach?
>

Its not exactly the same.  amount didn't use a pipe, it started the
connection with an fd, did the auth and then passes the fd to the
kernel to use.  The use of the pipe adds extra copies on all data
after authentication.  This is the overhead involved with the srv
approach that I mentioned.  IMHO it is worth it for the performance.
There's also the security implications of the srv approach, but I was
never really much concerned with that angle.

        -eric