Status of kdbus? was Re: Signal subscriptions dead on upgrade to Ubuntu Raring (13.04)

[Tim Sander]

Hi 
> > Do you have more info on this? As these KDBus guys have a rather strange
> > communication behaviour (e.g. not using this list?). But keeping politics
> > aside, having a faster (lower latency ) dbus would be really good.
> 
> Cool, another Thiago!
At least my name also starts with 'T' probably it would be the same for you if 
you where named Tennart ;-). But at least you're reading this list, so maybe i 
stand corrected.
> If you want to know what is going on in kdbus land, please follow the
> git repositories, that's where development takes place...
> 
> https://code.google.com/p/d-bus/source/list
> http://cgit.freedesktop.org/systemd/systemd/log/src/libsystemd-bus
Nice, will take a look as time permits.

> We'll post this for review to LKML and the dbus ML as soon as we
> actually have covered everything we need to cover.
> 
> In the past weeks we have been working on figuring out what we actually
> can do in the kernel regarding zero-copy stuff, both technically and
> politically.
Hopefully this will not get shoot down as the previous attempts.

> We have a scheme now that can do single-copy for small messages and
> zero-copy for large messages, which is pretty much the best possible
> outcome. Now we just need to hook this up everywhere...
> 
> (You can now send a large text file over kdbus with exactly 0 copies,
> how amazing is that? dbus-1 requires 5 copies for that...)
That sounds great. 5 copies *and* 5 context switches which may hurting latency 
even more.

Best regards
Tim