gh-90815: Add mimalloc memory allocator

Doc/c-api/init_config.rst

@@ -253,11 +253,21 @@ PyPreConfig
       * ``PYMEM_ALLOCATOR_PYMALLOC_DEBUG`` (``6``): :ref:`Python pymalloc
         memory allocator <pymalloc>` with :ref:`debug hooks
         <pymem-debug-hooks>`.
+      * ``PYMEM_ALLOCATOR_MIMALLOC`` (``6``): use ``mimalloc``, a fast
+        malloc replacement.
+      * ``PYMEM_ALLOCATOR_MIMALLOC_DEBUG`` (``7``): use ``mimalloc``, a fast
+        malloc replacement with :ref:`debug hooks <pymem-debug-hooks>`.
+
 
       ``PYMEM_ALLOCATOR_PYMALLOC`` and ``PYMEM_ALLOCATOR_PYMALLOC_DEBUG`` are
       not supported if Python is :option:`configured using --without-pymalloc
       <--without-pymalloc>`.
 
+      ``PYMEM_ALLOCATOR_MIMALLOC`` and ``PYMEM_ALLOCATOR_MIMALLOC_DEBUG`` are
+      not supported if Python is :option:`configured using --without-mimalloc
+      <--without-mimalloc>` or if the underlying atomic support isn't
+      available.
+
       See :ref:`Memory Management <memory>`.
 
       Default: ``PYMEM_ALLOCATOR_NOT_SET``.

Doc/c-api/memory.rst

@@ -379,8 +379,8 @@ Default memory allocators:
 ===============================  ====================  ==================  =====================  ====================
 Configuration                    Name                  PyMem_RawMalloc     PyMem_Malloc           PyObject_Malloc
 ===============================  ====================  ==================  =====================  ====================
-Release build                    ``"pymalloc"``        ``malloc``          ``pymalloc``           ``pymalloc``
-Debug build                      ``"pymalloc_debug"``  ``malloc`` + debug  ``pymalloc`` + debug   ``pymalloc`` + debug
+Release build                    ``"mimalloc"``        ``malloc``          ``mimalloc``           ``mimalloc``
+Debug build                      ``"mimalloc_debug"``  ``malloc`` + debug  ``mimalloc`` + debug   ``mimalloc`` + debug
 Release build, without pymalloc  ``"malloc"``          ``malloc``          ``malloc``             ``malloc``
 Debug build, without pymalloc    ``"malloc_debug"``    ``malloc`` + debug  ``malloc`` + debug     ``malloc`` + debug
 ===============================  ====================  ==================  =====================  ====================
@@ -391,6 +391,8 @@ Legend:
 * ``malloc``: system allocators from the standard C library, C functions:
   :c:func:`malloc`, :c:func:`calloc`, :c:func:`realloc` and :c:func:`free`.
 * ``pymalloc``: :ref:`pymalloc memory allocator <pymalloc>`.
+* ``mimalloc``: :ref:`mimalloc memory allocator <mimalloc>`.  The pymalloc
+  allocator will be used if mimalloc support isn't available.
 * "+ debug": with :ref:`debug hooks on the Python memory allocators
   <pymem-debug-hooks>`.
 * "Debug build": :ref:`Python build in debug mode <debug-build>`.
@@ -671,6 +673,18 @@ Customize pymalloc Arena Allocator
 
    Set the arena allocator.
 
+.. _mimalloc:
+
+The mimalloc allocator
+======================
+
+.. versionadded:: 3.13
+
+Python supports the mimalloc allocator when the underlying platform support is available.
+mimalloc "is a general purpose allocator with excellent performance characteristics.
+Initially developed by Daan Leijen for the runtime systems of the Koka and Lean languages."
+
+When mimalloc support is available it is the default allocator.
 
 tracemalloc C API
 =================

Doc/license.rst

@@ -1040,3 +1040,30 @@ https://www.w3.org/TR/xml-c14n2-testcases/ and is distributed under the
    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
+mimalloc
+--------
+
+MIT License
+
+Copyright (c) 2018-2021 Microsoft Corporation, Daan Leijen
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+

Doc/using/cmdline.rst

@@ -911,13 +911,17 @@ conflict.
    * ``pymalloc``: use the :ref:`pymalloc allocator <pymalloc>` for
      :c:macro:`PYMEM_DOMAIN_MEM` and :c:macro:`PYMEM_DOMAIN_OBJ` domains and use
      the :c:func:`malloc` function for the :c:macro:`PYMEM_DOMAIN_RAW` domain.
+   * ``mimalloc``: use the :ref:`mimalloc allocator <mimalloc>` for
+     :c:macro:`PYMEM_DOMAIN_MEM` and :c:macro:`PYMEM_DOMAIN_OBJ` domains and use
+     the :c:func:`malloc` function for the :c:macro:`PYMEM_DOMAIN_RAW` domain.
 
    Install :ref:`debug hooks <pymem-debug-hooks>`:
 
    * ``debug``: install debug hooks on top of the :ref:`default memory
      allocators <default-memory-allocators>`.
    * ``malloc_debug``: same as ``malloc`` but also install debug hooks.
    * ``pymalloc_debug``: same as ``pymalloc`` but also install debug hooks.
+   * ``mimalloc_debug``: same as ``mimalloc`` but also install debug hooks.
 
    .. versionchanged:: 3.7
       Added the ``"default"`` allocator.

Doc/using/configure.rst

@@ -579,6 +579,13 @@ also be used to improve performance.
    Enable computed gotos in evaluation loop (enabled by default on supported
    compilers).
 
+.. option:: --without-mimalloc
+
+   Disable the fast mimalloc allocator :ref:`mimalloc <mimalloc>`
+   (enabled by default).
+
+   See also :envvar:`PYTHONMALLOC` environment variable.
+
 .. option:: --without-pymalloc
 
    Disable the specialized Python memory allocator :ref:`pymalloc <pymalloc>`

Include/cpython/pymem.h

@@ -29,6 +29,10 @@ typedef enum {
     PYMEM_ALLOCATOR_PYMALLOC = 5,
     PYMEM_ALLOCATOR_PYMALLOC_DEBUG = 6,
 #endif
+#ifdef WITH_MIMALLOC
+    PYMEM_ALLOCATOR_MIMALLOC = 7,
+    PYMEM_ALLOCATOR_MIMALLOC_DEBUG = 8,
+#endif
 } PyMemAllocatorName;