[Python-Dev] profiler hooks (original) (raw)

Samuele Pedroni pedroni@inf.ethz.ch
Fri, 12 Oct 2001 23:19:14 +0200

Changes to bdb/pdb will probably be required, but I'm not sure yet. The biggest change I expect for debugging is that a 'return' event will be generated even when an exception is being propogated, but what this means is that the code that runs for the 'exception' event will not need to be so magical (this was why the old profiler results were so terribly difficult to interpret -- the times were often wrong depending on just how exceptions were handled in the application code). The recent changes to ceval.c for the profiler ensure that the profiler receives a 'return' event when control leaves a frame, even if an exception was set, and expception events are no longer reported to the profiler. This avoids the messy code needed to ensure the profiler accounted for timimg properly for 'exception' events, which is still quite fragile -- it works very hard just to make sure it doesn't lose track of the stack. Making the tracer also receive matching call/return events means that the exception events should no longer need to worry about stack management, which should make the code simpler. I don't know if Jython uses the same pdb.py as CPython, so I don't know what affects will show up there.

I know, and yes pdb.py worked with jython too, that's why I asked about the changes in the first place ... another to-do for jython 2.2

regards.