From 63108fd76738baeca2c5d58099c871481fa8d978 Mon Sep 17 00:00:00 2001
From: Vladislav Vaintroub <vvaintroub@gmail.com>
Date: Thu, 11 Jun 2026 16:35:24 +0200
Subject: [PATCH] MDEV-38369 improve heap allocation performance on Windows
 with segmentHeap

Use modern segmentHeap heap manager on Windows.

The problem it is solving is severily reduced scalability on concurrent
OLTP benchmarks, due to inherent scalability problems in default NT Heap
implementation.

The benchmarks (see the corresponding ticket) show improvements across
the board, with about 5-10% on low concurrency up to several orders of
magnitude on high concurrency.

Also addressed Gemini and Copilot concerns about correct namespace in
the app manifest XML file - make it the same as in Microsoft examples.
---
 cmake/win_compatibility.manifest | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/cmake/win_compatibility.manifest b/cmake/win_compatibility.manifest
index 0e7ce667d68d0..62ce650318097 100644
--- a/cmake/win_compatibility.manifest
+++ b/cmake/win_compatibility.manifest
@@ -19,9 +19,10 @@
 
     </application>
   </compatibility>
-  <application>
+  <application xmlns="urn:schemas-microsoft-com:asm.v3">
     <windowsSettings>
       <activeCodePage xmlns="http://schemas.microsoft.com/SMI/2019/WindowsSettings">UTF-8</activeCodePage>
+      <heapType xmlns="http://schemas.microsoft.com/SMI/2020/WindowsSettings">SegmentHeap</heapType>
     </windowsSettings>
   </application>
 </asmv1:assembly>