The replaces the incremental GC with a forward port (from 3.13) of the generational GC.
Co-Authored-By: Neil Schemenauer <[email protected]>
Co-Authored-By: Zanie Blue <[email protected]>
Co-Authored-By: Sergey Miryanov <[email protected]>
Co-authored-by: Hugo van Kemenade <[email protected]>
The gc_stats struct contains ring buffers of gc_generation_stats
entries (11 young + 3×2 old on default builds). Embedding it inline
in _gc_runtime_state, which is itself inline in PyInterpreterState,
pushed fields like _gil.locked and threads.head to offsets beyond
what out-of-process profilers and debuggers can reasonably read in
a single buffer (e.g. offset 9384 for _gil.locked vs an 8 KiB read
buffer).
Heap-allocate generation_stats via PyMem_RawCalloc in _PyGC_Init and
free it in _PyGC_Fini. This shrinks PyInterpreterState by ~1.6 KiB
and keeps the GIL, thread-list, and other frequently-inspected fields
at stable, low offsets.
* Promote _PyObject_Dump() as a public function.
* Keep _PyObject_Dump() alias to PyUnstable_Object_Dump()
for backward compatibility.
* Replace _PyObject_Dump() with PyUnstable_Object_Dump().
Co-authored-by: Peter Bierma <[email protected]>
Co-authored-by: Kumar Aditya <[email protected]>
Co-authored-by: Petr Viktorin <[email protected]>
- Introduce a new field in the GC state to store the frame that initiated garbage collection.
- Update RemoteUnwinder to include options for including "<native>" and "<GC>" frames in the stack trace.
- Modify the sampling profiler to accept parameters for controlling the inclusion of native and GC frames.
- Enhance the stack collector to properly format and append these frames during profiling.
- Add tests to verify the correct behavior of the profiler with respect to native and GC frames, including options to exclude them.
Co-authored-by: Pablo Galindo Salgado <[email protected]>
Allow the --enable-pystats build option to be used with free-threading. The
stats are now stored on a per-interpreter basis, rather than process global.
For free-threaded builds, the stats structure is allocated per-thread and
then periodically merged into the per-interpreter stats structure (on thread
exit or when the reporting function is called). Most of the pystats related
code has be moved into the file Python/pystats.c.
* Count number of actually tracked objects, instead of trackable objects. This ensures that untracking tuples has the desired effect of reducing GC overhead
* Do not track most untrackable tuples during creation. This prevents large numbers of small tuples causing execessive GCs.
Fix a bug caused by the garbage collector clearing weakrefs too early. The
weakrefs in the ``tp_subclasses`` dictionary are needed in order to correctly
invalidate type caches (for example, by calling ``PyType_Modified()``).
Clearing weakrefs before calling finalizers causes the caches to not be
correctly invalidated. That can cause crashes since the caches can refer to
invalid objects. Defer the clearing of weakrefs without callbacks until after
finalizers are executed.
In GH-116206, the comment about moving reachable objects to next generation
got moved from its original place to a place where there is no code below
it. Put the comment back to where the actual movement of reachable objects
happens.
Weakrefs to unreachable garbage that are created during running of
finalizers need to be cleared. This avoids exposing objects that
have `tp_clear` called on them to Python-level code.
Optimize `LOAD_FAST` opcodes into faster versions that load borrowed references onto the operand stack when we can prove that the lifetime of the local outlives the lifetime of the temporary that is loaded onto the stack.
Minor readability fix in PyUnstable_GC_VisitObjects
Replaces `if (visit_generation())` with `if (visit_generation() < 0)`,
since we are checking for the failure case, and it's confusing to have
that be implicitly `true`.
Also fixes a misspelt variable name.
The reference count fields, such as `ob_tid` and `ob_ref_shared`, may be
accessed concurrently in the free threading build by a `_Py_TryXGetRef`
or similar operation. The PyObject header fields will be initialized by
`_PyObject_Init`, so only call `memset()` to zero-initialize the remainder
of the allocation.
* Mark almost all reachable objects before doing collection phase
* Add stats for objects marked
* Visit new frames before each increment
* Update docs
* Clearer calculation of work to do.
* Mark almost all reachable objects before doing collection phase
* Add stats for objects marked
* Visit new frames before each increment
* Remove lazy dict tracking
* Update docs
* Clearer calculation of work to do.
Fix a bug that can cause a crash when sub-interpreters use "basic"
single-phase extension modules. Shared objects could refer to PyGC_Head
nodes that had been freed as part of interpreter shutdown.
Use a `_PyStackRef` and defer the reference to `f_executable` when
possible. This avoids some reference count contention in the common case
of executing the same code object from multiple threads concurrently in
the free-threaded build.
