From e3cf5fa9246c4b38cd5342ad6d60dd359d1e8cb6 Mon Sep 17 00:00:00 2001
From: Pieter Eendebak <pieter.eendebak@gmail.com>
Date: Tue, 5 May 2026 20:51:01 +0200
Subject: [PATCH 1/4] inspect: fast path _shadowed_dict for type

---
 Lib/inspect.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Lib/inspect.py b/Lib/inspect.py
index d3af61b26e280a..344933ce4b1b9f 100644
--- a/Lib/inspect.py
+++ b/Lib/inspect.py
@@ -1740,6 +1740,9 @@ def _shadowed_dict(klass):
     # destroyed, and the dynamically created classes happen to be the only
     # objects that hold strong references to other objects that take up a
     # significant amount of memory.
+    # Fast path: `type` is the dominant caller; result is always _sentinel.
+    if klass is type:
+        return _sentinel
     return _shadowed_dict_from_weakref_mro_tuple(
         *[make_weakref(entry) for entry in _static_getmro(klass)]
     )

From dbd9fcf4970db7acde5368b0ac7c4adadc73ef38 Mon Sep 17 00:00:00 2001
From: Pieter Eendebak <pieter.eendebak@gmail.com>
Date: Tue, 5 May 2026 21:18:30 +0200
Subject: [PATCH 2/4] inspect: cache last metaclass in _check_class MRO loop

Consecutive MRO entries usually share their metaclass, so call
_shadowed_dict at most once per distinct metaclass.
---
 Lib/inspect.py | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/Lib/inspect.py b/Lib/inspect.py
index 344933ce4b1b9f..b2d105cffa20ec 100644
--- a/Lib/inspect.py
+++ b/Lib/inspect.py
@@ -1706,9 +1706,13 @@ def _check_instance(obj, attr):
 
 
 def _check_class(klass, attr):
+    last_meta = None
     for entry in _static_getmro(klass):
-        if _shadowed_dict(type(entry)) is _sentinel and attr in entry.__dict__:
-            return entry.__dict__[attr]
+        meta = type(entry)
+        if meta is last_meta or _shadowed_dict(meta) is _sentinel:
+            last_meta = meta
+            if attr in entry.__dict__:
+                return entry.__dict__[attr]
     return _sentinel
 
 

From c45e06f03d870056c3bb04d97ca5503089dc1d5e Mon Sep 17 00:00:00 2001
From: "blurb-it[bot]" <43283697+blurb-it[bot]@users.noreply.github.com>
Date: Fri, 8 May 2026 14:24:25 +0000
Subject: [PATCH 3/4] =?UTF-8?q?=F0=9F=93=9C=F0=9F=A4=96=20Added=20by=20blu?=
 =?UTF-8?q?rb=5Fit.?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../next/Library/2026-05-08-14-24-16.gh-issue-149436.dEV02X.rst  | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 Misc/NEWS.d/next/Library/2026-05-08-14-24-16.gh-issue-149436.dEV02X.rst

diff --git a/Misc/NEWS.d/next/Library/2026-05-08-14-24-16.gh-issue-149436.dEV02X.rst b/Misc/NEWS.d/next/Library/2026-05-08-14-24-16.gh-issue-149436.dEV02X.rst
new file mode 100644
index 00000000000000..4dfcec001cbe3b
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2026-05-08-14-24-16.gh-issue-149436.dEV02X.rst
@@ -0,0 +1 @@
+Improve performance of :method:`inspect.getattr_static`.

From 2ff4a2a9b1033e8bed712e081f93bafd370cc602 Mon Sep 17 00:00:00 2001
From: Pieter Eendebak <pieter.eendebak@gmail.com>
Date: Fri, 8 May 2026 18:27:24 +0200
Subject: [PATCH 4/4] Apply suggestion from @eendebakpt

---
 .../next/Library/2026-05-08-14-24-16.gh-issue-149436.dEV02X.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Misc/NEWS.d/next/Library/2026-05-08-14-24-16.gh-issue-149436.dEV02X.rst b/Misc/NEWS.d/next/Library/2026-05-08-14-24-16.gh-issue-149436.dEV02X.rst
index 4dfcec001cbe3b..401cf044e1514f 100644
--- a/Misc/NEWS.d/next/Library/2026-05-08-14-24-16.gh-issue-149436.dEV02X.rst
+++ b/Misc/NEWS.d/next/Library/2026-05-08-14-24-16.gh-issue-149436.dEV02X.rst
@@ -1 +1 @@
-Improve performance of :method:`inspect.getattr_static`.
+Improve performance of :meth:`inspect.getattr_static`.