New submission from Xavier de Gaye: When f_trace is NULL, only PyTrace_CALL tracing events trigger the invocation of the trace function (see trace_trampoline). maybe_call_line_trace() does quite some work though _PyCode_CheckLineNumber to find out if the instruction should be traced, and all this work is useless when f_trace is NULL. The patch checks for f_trace on all tracing events that are not PyTrace_CALL.
The performance gain with the following test is about 30%. The first test is with python on the default branch, the second one with the patch applied. Note: a breakpoint is set at line 1 to ensure that tracing is enabled, without any breakpoint, pdb sets the trace function to None after a continue. $ ./python -m pdb /tmp/foo.py > /tmp/foo.py(1)<module>() -> import timeit (Pdb) break 1 Breakpoint 1 at /tmp/foo.py:1 (Pdb) continue 9.226385930000106 The program finished and will be restarted > /tmp/foo.py(1)<module>() -> import timeit (Pdb) q [62276 refs] $ ./python -m pdb /tmp/foo.py > /tmp/foo.py(1)<module>() -> import timeit (Pdb) break 1 Breakpoint 1 at /tmp/foo.py:1 (Pdb) continue 7.199809867001022 The program finished and will be restarted > /tmp/foo.py(1)<module>() -> import timeit (Pdb) ---------- components: Interpreter Core files: f_trace_perfs.diff keywords: patch messages: 177390 nosy: xdegaye priority: normal severity: normal status: open title: improve tracing performances when f_trace is NULL type: enhancement versions: Python 3.4 Added file: http://bugs.python.org/file28297/f_trace_perfs.diff _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue16672> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
