From 7ac9918b393788aa0d18da39dcc066357c4d6dae Mon Sep 17 00:00:00 2001
From: Philip Rebohle <philip.rebohle@tu-dortmund.de>
Date: Wed, 25 Sep 2024 00:11:24 +0200
Subject: [PATCH] [hud] Add cache statistics to detailed memory item

---
 src/dxvk/hud/dxvk_hud_item.cpp | 24 +++++++++++++++++++++++-
 src/dxvk/hud/dxvk_hud_item.h   |  7 ++++++-
 2 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/src/dxvk/hud/dxvk_hud_item.cpp b/src/dxvk/hud/dxvk_hud_item.cpp
index ece35086f..2032cf18d 100644
--- a/src/dxvk/hud/dxvk_hud_item.cpp
+++ b/src/dxvk/hud/dxvk_hud_item.cpp
@@ -652,7 +652,14 @@ namespace dxvk::hud {
 
 
   void HudMemoryDetailsItem::update(dxvk::high_resolution_clock::time_point time) {
-    m_device->getMemoryAllocationStats(m_stats);
+    uint64_t ticks = std::chrono::duration_cast<std::chrono::microseconds>(time - m_lastUpdate).count();
+
+    if (ticks >= UpdateInterval) {
+      m_cacheStats = m_device->getMemoryAllocationStats(m_stats);
+      m_displayCacheStats |= m_cacheStats.requestCount != 0u;
+
+      m_lastUpdate = time;
+    }
   }
 
 
@@ -702,6 +709,9 @@ namespace dxvk::hud {
       pos.y -= 30.0f + 4.0f;
     }
 
+    if (m_displayCacheStats)
+      pos.y -= 20.0f;
+
     // Actually render the thing
     for (uint32_t i = 0; i < m_stats.memoryTypes.size(); i++) {
       const auto& type = m_stats.memoryTypes.at(i);
@@ -747,6 +757,18 @@ namespace dxvk::hud {
       pos.y += 46.0f;
     }
 
+    if (m_displayCacheStats) {
+      uint32_t hitCount = m_cacheStats.requestCount - m_cacheStats.missCount;
+      uint32_t hitRate = (100 * hitCount) / std::max(m_cacheStats.requestCount, 1u);
+
+      std::string cacheStr = str::format("Cache: ", m_cacheStats.size >> 10, " kB (", hitRate, "% hit)");
+
+      renderer.drawText(14.0f,
+        { pos.x, pos.y },
+        { 1.0f, 1.0f, 1.0f, 1.0f },
+        cacheStr);
+    }
+
     return position;
   }
 
diff --git a/src/dxvk/hud/dxvk_hud_item.h b/src/dxvk/hud/dxvk_hud_item.h
index b5fef160b..9516629b8 100644
--- a/src/dxvk/hud/dxvk_hud_item.h
+++ b/src/dxvk/hud/dxvk_hud_item.h
@@ -394,7 +394,7 @@ namespace dxvk::hud {
    * \brief HUD item to display detailed memory allocation info
    */
   class HudMemoryDetailsItem : public HudItem {
-
+    constexpr static int64_t UpdateInterval = 500'000;
   public:
 
     HudMemoryDetailsItem(const Rc<DxvkDevice>& device);
@@ -421,6 +421,11 @@ namespace dxvk::hud {
 
     Rc<DxvkDevice>                    m_device;
     DxvkMemoryAllocationStats         m_stats;
+    DxvkSharedAllocationCacheStats    m_cacheStats;
+
+    high_resolution_clock::time_point m_lastUpdate = { };
+
+    bool                m_displayCacheStats = false;
 
     Rc<DxvkShader>      m_vs;
     Rc<DxvkShader>      m_fsBackground;