Re: [PATCH 0/11] LTTng-core (basic tracing infrastructure) 0.5.108

["Jose R. Santos" <jrs@us.ibm.com>]

Mathieu Desnoyers wrote:
> * Andrew Morton (akpm@osdl.org) wrote:
> > Of course, it they are properly designed, the one set of tracepoints could
> > be used by different tracing backends - that allows us to separate the
> > concepts of "tracepoints" and "tracing backends".
>
> If I try to develop your idea a little further, we could this of dividing the
> tracing problem into four layers :
>
> - tracepoints (where the code is instrumented)
>   - identifying code
>   - accessing data surrounding the code
> - tracing backend (how to add the tracepoints)
> - tracing infrastructure (what code will serialize the information)
> - data extraction (getting the data out to disk, network, ...)
>   

I think you missing user-space post processing which should be also 
considered part of the problem since the capabilities of post-processing 
will be limited by the "tracepoints" available.  Tracepoints and 
post-processing are also the problems which need to be address first 
between the other established tracing projects before going forward with 
in-kernel solutions.

> I think that, if we agree on this segmentation of the problem, this thread is
> generally debating on the tracing backends and their respective limitations.
> I just want to point out that the patch I have submitted adresses mainly the
> "tracing infrastructure" and "data extraction" topics.
>   

This seem like a good idea to dissect the problem since it seem like 
other important issues relevant to general tracing are being ignore 
simply because of a dislike of the way LTTng has chosen to implement trace.

-JRS