Re: [linuxtools-dev] LTTng question

[William Bourque <william.bourque@xxxxxxxxxx>]

Mathieu Desnoyers wrote:
> * William Bourque (william.bourque@xxxxxxxxxx) wrote:
>> Xavier RAYNAUD wrote:
> 
> [...]
> 
>>> I guess I've compiled a wrong version of LTTv application ?
>>> Which one should I use instead ?
>>
>> Hi,
>>
>> The help files and the instruction are (already?) a bit outdated, as
>> well as the sample trace given with the plugin. The traces currently
>> given with the plugin are no longer compatible with the reading code.
>> The traces should have been changed already, we will make sure to push
>> new sample traces today (and to remove the old one). You could also
>> record one if you have installed the latest Lttng kernel patches.
>>
>> Also, make sure to use the latest version of the Lttv C library (you
>> better use the one at
>> http://git.dorsal.polymtl.ca/?p=liblttngtrace.git;a=summary  for now,
>> some changes are not yet been pushed to the main tree).
>>
>> Sorry about that, we kind of forgot about these.
>>
>>
>>
>> To tell you the exact technical details, what's happen is that our
>> Eclipse plugin use some JNI code to load the C library that handle
>> parsing and/or moving in the traces. It's the library that is giving you
>> the warnings and debug information you see.
>> The library itself is part of the Lttv application and is developped by
>> another open source project (lttng.org) not related to linuxtools or
>> Eclipse. The problem that this team recently decide to change their
>> trace format, so our old trace are no longer supported by their library.
>> We had already planned to support multiple trace version at the same
>> time but it's not ready yet so for now we decide to stick with their
>> latest version. We are currently working with the Lttng.org team so they
>> add what we need in their library to support multiple trace format,
>> hopefully it should be ready for the next release of linuxtools.
> 
> Hi William,
> 
> You should probably create your own "compatibility list" which you post
> on a website so your users (and yourself) remember which versions fit
> together in the future. Saying "use the latest version" is vague and
> does not tell much when someone read a mailing list archive one month in
> the future.

Hi,

You are right and it's already planned to have it for the official
release of the Eclipse Lttng plugin in linuxtools.
It's quite hard to do for now, however, as we are playing with
developpement versions of everything (TMF, Eclipse Lttng and JNI hooks
in Lttv). The APIs are not yet fixed so "compatible versions" change on
a weekly basis, it is just not possible to keep track of all changes for
now.
"Latest of everything" is the best answer we can give for now,
especially since a lot of these things have not official versionning out
of the SVN timestamp.

- William

> 
> Thanks,
> 
> Mathieu
> 
>