From ca4c03284fa2308675176417d43badef9a2e8fe7 Mon Sep 17 00:00:00 2001
From: Philip Rebohle <philip.rebohle@tu-dortmund.de>
Date: Tue, 28 Jan 2020 12:33:37 +0100
Subject: [PATCH] [dxvk] Don't oversubscribe memory heaps on UMA devices

Otherwise, we seem to suffer a major performance penalty
on setups with insufficient dedicated system memory.
---
 src/dxvk/dxvk_memory.cpp | 5 +++++
 src/dxvk/dxvk_memory.h   | 2 ++
 2 files changed, 7 insertions(+)

diff --git a/src/dxvk/dxvk_memory.cpp b/src/dxvk/dxvk_memory.cpp
index 3ebe5f0e..11f2dfa1 100644
--- a/src/dxvk/dxvk_memory.cpp
+++ b/src/dxvk/dxvk_memory.cpp
@@ -169,6 +169,8 @@ namespace dxvk {
       m_memTypes[i].memTypeId  = i;
       m_memTypes[i].chunkSize  = pickChunkSize(i);
     }
+
+    m_restrictAllocations = m_device->isUnifiedMemoryArchitecture();
   }
   
   
@@ -309,6 +311,9 @@ namespace dxvk {
     bool useMemoryPriority = (flags & VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT)
                           && (m_device->features().extMemoryPriority.memoryPriority);
     
+    if (m_restrictAllocations && type->heap->stats.memoryAllocated + size > type->heap->properties.size)
+      return DxvkDeviceMemory();
+
     DxvkDeviceMemory result;
     result.memSize  = size;
     result.memFlags = flags;
diff --git a/src/dxvk/dxvk_memory.h b/src/dxvk/dxvk_memory.h
index 8034c361..92719501 100644
--- a/src/dxvk/dxvk_memory.h
+++ b/src/dxvk/dxvk_memory.h
@@ -284,6 +284,8 @@ namespace dxvk {
     std::mutex                                      m_mutex;
     std::array<DxvkMemoryHeap, VK_MAX_MEMORY_HEAPS> m_memHeaps;
     std::array<DxvkMemoryType, VK_MAX_MEMORY_TYPES> m_memTypes;
+
+    bool m_restrictAllocations;
     
     DxvkMemory tryAlloc(
       const VkMemoryRequirements*             req,