[Samba] Asynchronous I/O

[Andy Liebman]

Thanks, Jeremy!

Andy
> Currently aio on Linux is horribly broken due to a conservative
> glibc, which limits asynchronous requests to one outstanding one
> per file descriptor (which pretty much makes all io synchronous
> on Linux, whether you set aio sizes or not :-( ). I think this
> is a bug which needs fixing but haven't yet had time to do the
> work to prove this to glibc maintanence. This will be increasingly
> important for SMB2, as the Windows redirector now properly
> pipelines io (which the SMB1 redirector doesn't).
>
> Currently the only way to get real aio on Linux is to use
> Volker's vfs_aio_fork module, which uses processes to get
> true async io working. Volker is also doing a lot of work
> making aio work correctly on Linux (he has a git branch
> you can track for this). Should be working properly in
> 3.6.x and above (that's the plan :-).
>
>