[lttng-dev] [RFC] Dynamic instrumentation support in UST

[Thibault, Daniel]

-----Message d'origine-----
Envoyé : 30 juillet 2013 09:26

> If we use the command line interface you described, like
>      lttng enable-event --processname a.out
> Then we will need a mechanism to distinguish processes with the same name. For example, I want to instrument my program for debugging but not touch any processes in production.

   That's an odd use case you're describing.  If one wanted to trace specific process instances, one would naturally use PIDs instead of process names.  (Maybe the PID command option could accept enumerations of PIDs, i.e. something like 'lttng whatever --pid={123, 456, 789}')  If one did not know the PIDs in advance (hence the reliance on process names), then the solution would be to use filters on the events, no?  Your to-be-debugged program could be run with an environment (or internal global variable) setting that the filters could check, for instance.

   In the near future, one could use namespaces to isolate the production instances from the experimental ones.

Daniel U. Thibault
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