Starting the kdbus discussions

[Lennart Poettering]

On Fri, 17.01.14 11:21, David Zeuthen (zeuthen at gmail.com) wrote:

> 
> Hey,
> 
> On Fri, Jan 17, 2014 at 10:06 AM, Lennart Poettering <mzqohf at 0pointer.de> wrote:
> > I am pretty sure that the dbus thread gdbus uses is a poor design
> > choice. It introduces extra latency for starters. However, what's
> > particularly bad about it is that it really breaks any attempts of
> > teaching gdbus prio inheritance magic.
> 
> Sigh. Sorry, but that's a pretty dumb thing to say especially as these
> synthetic benchmarks (how exciting they may be) do not at all reflect
> how D-Bus is used. Let me explain. The reason for GDBus using a
> worker-thread has to do with ease-of-use in both multi-threaded
> event-driven applications (e.g. using a main-loop mechanism and async,
> callback-based facilities to send/receive D-Bus messages and
> worker-threads using sync D-Bus facilities to send/receive) as well as
> command-line programs where you don't have a main-loop at all.
> 
> IOW, the trade-off was well known at the time - saying it's poor
> design just reflects poor knowledge of exactly what problems GDBus set
> out to solve, and, IMHO, ended up solving very nicely.

Well, libdbus1 covers both usecases too, no? What does the worker thread
bring as a benefit over the way libdbus1 handles this?

Lennart

-- 
Lennart Poettering, Red Hat