GH-91636: Clear weakrefs created by finalizers. (GH-136401)
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.
(cherry picked from commit b6b99bf7f1)
Co-authored-by: Neil Schemenauer <nas-github@arctrix.com>
* 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.
gh-136517: Print uncollectable objects if DEBUG_UNCOLLECTABLE mode was set (GH-136518)
(cherry picked from commit c560df9658)
Co-authored-by: Sergey Miryanov <sergey.miryanov@gmail.com>
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.
The free-threaded GC now visits interpreter stacks to keep objects
that use deferred reference counting alive.
Interpreter frames are zero initialized in the free-threaded GC so
that the GC doesn't see garbage data. This is a temporary measure
until stack spilling around escaping calls is implemented.
Co-authored-by: Ken Jin <kenjin@python.org>
Use the new public Raw functions:
* _PyTime_PerfCounterUnchecked() with PyTime_PerfCounterRaw()
* _PyTime_TimeUnchecked() with PyTime_TimeRaw()
* _PyTime_MonotonicUnchecked() with PyTime_MonotonicRaw()
Remove internal functions:
* _PyTime_PerfCounterUnchecked()
* _PyTime_TimeUnchecked()
* _PyTime_MonotonicUnchecked()
Change old space bit of young objects from 0 to gcstate->visited_space.
This ensures that any object created *and* collected during cycle GC has the bit set correctly.
<pycore_time.h> include is no longer needed to get the PyTime_t type
in internal header files. This type is now provided by <Python.h>
include. Add <pycore_time.h> includes to C files instead.
Sergey Miryanov