review request: sendfile kqueue notification

[Adrian Chadd]

And yes, I know this breaks the 32 bit compat sendfile call. I'm
thinking of how to fix this without just duplicating all of that code.

Thanks,



-a

On 12 December 2013 12:41, Adrian Chadd <adrian at freebsd.org> wrote:
> Hi,
>
> I'd like to start committing this to FreeBSD-HEAD:
>
> http://people.freebsd.org/~adrian/netflix/20131211-sendfile-kqueue-11.diff
>
> It implements kqueue notifications for sendfile so users can get an
> asynchronous notification that the underlying mbufs have been freed.
> This allows userland users of sendfile to know that the underlying
> memory / file object can be recycled or overwritten. Right now the
> only way to do this is to set SF_SYNC and this causes sendfile() to
> sleep until the transaction is complete and the mbufs have been freed.
>
> I've been testing this out locally in my lab environment and it's
> running flawlessly at 30gbit/sec of TCP across 32,768 active
> transmitting sockets.
>
> I'd like to start merging this into -HEAD in small pieces to make it
> easier to MFC to -10.
>
> Thanks!
>
>
>
> -adrian