Add section on static code objects/freezing imports

Co-Authored-By: Kumar Aditya <59607654+kumaraditya303@users.noreply.github.com>
python · Fidget-Spinner · Apr 6, 2022 · Mar 8, 2022 · Mar 25, 2022 · Mar 25, 2022
commit 77701feba07ed673948bdfe8c64d8c5a44444540
diff --git a/Doc/tutorial/modules.rst b/Doc/tutorial/modules.rst
@@ -209,6 +209,8 @@ directory. This is an error unless the replacement is intended.  See section
 .. %
     Do we need stuff on zip files etc. ? DUBOIS
 
+.. _tut-pycache:
+
 "Compiled" Python files
 -----------------------
 

diff --git a/Doc/whatsnew/3.11.rst b/Doc/whatsnew/3.11.rst
@@ -425,11 +425,29 @@ runtime. Other optimizations not under this project are listed in `Optimizations
 Faster Startup
 --------------
 
-Static objects
-~~~~~~~~~~~~~~
+Frozen imports / Static code objects
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-Freezing imports
-~~~~~~~~~~~~~~~~
+Python caches bytecode in the :ref:`__pycache__<tut-pycache>` directory to
+speed up module loading.
+
+Previously in 3.10, Python module execution looked like this:
+
+.. code-block:: text
+
+   Read __pycache__ -> Unmarshal -> Heap allocated code object -> Evaluate
+
+In Python 3.11, the core modules essential for Python startup are "frozen".
+This means that their code objects (and bytecode) are statically allocated
+by the interpreter. This reduces the steps in module execution process to this:
+
+.. code-block:: text
+
+   Statically allocated code object -> Evaluate
+
+Interpreter startup is now 10-15% faster in Python 3.11.
+
+(Contributed by Eric Snow, Guido van Rossum and Kumar Aditya in numerous issues.)
 
 
 Faster Runtime
-Original file line number
+Diff line change
@@ Expand Up @@
     .. %
         Do we need stuff on zip files etc. ? DUBOIS
+    .. _tut-pycache:
     "Compiled" Python files
     -----------------------
@@ Expand Down @@