Logging environment variables¶
PyPy, and all other RPython programs, support some special environment variables used to tweak various advanced parameters.
PYPYLOG environment variable enables debugging output. For
means enabling all debugging output from the JIT, and writing to a
log. More precisely, the condition
enabling output of all sections whose name start with
interesting names to use here are
gc to get output from the GC, or
jit-backend to get only output from the JIT’s machine code
backend. It is possible to use several prefixes, like in the
which outputs sections containing to the optimized loops plus anything produced from the JIT backend. The above example is what you need for jitviewer.
The filename can be given as
- to dump the log to stderr.
As a special case, the value
PYPYLOG=+filename means that only
the section markers are written (for any section). This is mostly
only useful for
Only available in
pypy-stm. Names a log file into which the
PyPy-STM will output contention information. Can be read with