[lttng-dev] Need some advice/tips for hacking lttng-analyses

[Joel Fernandes]

Hi Julien, Mathieu and all,

I see lttng-analyses has done a lot of what we're starting to try to
do when parsing Android traces and I'd like to leverage that.

Currently in Android we just deal with text traces (ftrace stored in
an html file) - Its hard to move away from that given its popularity
and it seems to work well for our usecases (the trace format itself is
another discussion though).

We've started to use LISA to parse them to do analyses. Currently
though the analyses is primitive (build a DataFrame out of traces,
join the frames and apply a function). However I extended this to be
able to use callbacks since that seems much more flexible:

TraceCallback('<path to html>',  { 'sched_switch':
sched_switch_callback, 'sched_wakeup': sched_wakeup_callback })

Do you have any thoughts about the easiest way to get lttng-analyses
to work with a different 'backend' other than CTF? I am willing spend
time to hack it but I request you for any thoughts on where to start
hacking (which classes, files etc). I appreciate any tips from you
that can help me get a headstart.

IOW, I have a backend + callbacks to call (callbacks written in
Python). I want to use lttng-analyses to analyze the data passed to
the callbacks and reuse all the existing stuff in it.

Thanks a lot!

-Joel