Re: [linuxtools-dev] TCF and remote profiling

[Francois Chouinard <fchouinard@xxxxxxxxx>]

Hello Jeff,

Comments below.

On Thu, May 19, 2011 at 4:10 PM, Jeff Johnston <jjohnstn@xxxxxxxxxx> wrote:
> Hi Francois,
>
> I have been working on reviewing the remote Valgrind work that Elliott
> implemented before he finished his term here at Red Hat.  It uses TCF. In
> getting it to work I had to do some back-flips as I was using the TCF code
> found in DSDP, but I think it has potential (e.g. the remote valgrind
> implementation used the TCF agent provided without any enhancements
> required).  Set up seems to be the biggest hurdle at this point, but I
> believe that could be ironed out.
>

I totally agree with you. This essentially matches our experience with
an "enhanced" TCF agent running on the LTTng-instrumented target node.

> Another one of our interns, Lukas Berk, recently attended an LTTng
> conference call and asked a few questions on my behalf.  I was interested in
> one response which said that LTTng was not using TCF anymore because it was
> proprietary.  Did he interpret this correctly and if so, can you give more
> details?  The code in DSDP is EPL'd so at worst case it should be modifiable
> barring any patent issues.
>

LTTng *is* using TCF today and for the foreseeable future (at least months :-)).

I'm not sure I was on that particular call but I heard similar
confusing statements about the "proprietedness" of TCF. My
understanding is that TCF itself is EPL and that some tool vendor(s)
are building proprietary protocols/tools over it which is (1) not the
same story at all, and (2) totally legit.

Also, you are right that, if things turn sour, there's always the
possibility of simply fork the EPL code and handle it from there.

> Regarding TCF, I believe it is supposed to move to the CDT but I haven't
> seen it appear there yet.  If you know more details, please let me know.
>

TCF will be included in CDT 8.0 (Indigo). You can install it from any
recent developer nightly build or CDT RC1. In fact, we (LTTng) already
have a dependency on it in the Linux Tools project (causing some mild
headaches to Andrew in the precess :-)).

> -- Jeff J.
>
>
>

Hope this answers your questions

Regards,

-- 
Francois