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

Jose R. Santos
2006-09-15T20:27:56Z

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