[Spice-devel] RFC: Lightweight tracing mechanism

[Marc-André Lureau]

----- Original Message -----
> 
> > On 9 Jun 2017, at 17:16, Jonathon Jongsma <jjongsma at redhat.com> wrote:
> > 
> > On Fri, 2017-06-09 at 10:59 +0200, Christophe de Dinechin wrote:
> >>>> What I see on the thread:
> >>>> - log categorization. This was similar to Djasa bug but I think
> >>>> he just
> >>>>   proposed to use domains in the glib log sense;
> >> 
> >> Punchcard analogy: “Printer sheet categorization. This was similar to
> >> the report that Djisktra had taken McCarthy's listing by mistake"
> >> 
> >> I thought it was a good idea to derive glib log domains automatically
> >> from spice-traces.def. So it’s there in the branch now. That being
> >> said, as noted above, glib does linear searches on domain names, so
> >> this does not scale well. In the long term, we may want to have a
> >> separate field in a structured log.
> > 
> > 
> > Responding only to this point for the moment: I don't think using
> > multiple glib logging domains is necessarily desirable. We already use
> > several logging domains, but the vast majority of logging statements
> > within each project use a single domain. In spice-server, that primary
> > log domain is "Spice", and in spice-gtk that domain is "GSpice". spice-
> > server also has some additional domains like "SpiceWorker" and
> > "SpiceDispatcher". spice-gtk also has GSpiceController (which isn't
> > really used much these days).
> > 
> > The problem is that both spice-server and spice-gtk have a way to
> > enable debugging with an environment variable. But the code for
> > enabling the debugging only actually enables the primary domain.
> 
> The ‘traces’ branch enables all trace-related domains if you enable debug.
> 
> > So anything that is logged under a different domain does not get enabled.
> > (In fact, spice-gtk has 2 ways to enable logging with an environment
> > variable but one of the methods is the same one used for spice-server,
> > but it doesn't work since it actually enables logging for the "Spice"
> > domain which spice-gtk doesn't use.) I'm hoping to send some patches to
> > clean up this mess soon.
> 
> Ah, so I was not the only one thinking this was a mess :-)

The mess comes because spice-gtk and spice server used different logging, when spice didn't depend on glib.

The cleanup isn't over I suppose (Christophe F. did the move to glog in spice-common). 

I don't get the problem with spice-gtk logging though.

>