SL-17997 Follow up from beta breakers results.

3 files changed, 44 insertions, 33 deletions

diff --git a/indra/llrender/llimagegl.cpp b/indra/llrender/llimagegl.cpp
index ae10142e7a..7ba0cc2fde 100644
--- a/indra/llrender/llimagegl.cpp
+++ b/indra/llrender/llimagegl.cpp
@@ -54,7 +54,6 @@ const F32 MIN_TEXTURE_LIFETIME = 10.f;
 U32 wpo2(U32 i);
 
 
-#if LL_DARWIN
 // texture memory accounting (for OS X)
 static LLMutex sTexMemMutex;
 static std::unordered_map<U32, U32> sTextureAllocs;
@@ -119,22 +118,6 @@ U64 LLImageGL::getTextureBytesAllocated()
     return sTextureBytes;
 }
 
-#else
-
-#define alloc_tex_image(width, height, pixformat) (void) width; (void) height; (void) pixformat;
-#define free_tex_image(texName) (void) texName;
-#define free_tex_images(count, texNames) (void) count; (void) texNames;
-#define free_cur_tex_image()
-
-// static 
-U64 LLImageGL::getTextureBytesAllocated()
-{
-    // UNIMPLEMENTED OUTSIDE OF OS X, DO NOT CALL
-    llassert(false);
-    return 0;
-}
-#endif
-
 //statics
 
 U32 LLImageGL::sUniqueCount				= 0;
diff --git a/indra/llrender/llimagegl.h b/indra/llrender/llimagegl.h
index 619421e68a..1bcdd040e0 100644
--- a/indra/llrender/llimagegl.h
+++ b/indra/llrender/llimagegl.h
@@ -53,7 +53,10 @@ class LLImageGL : public LLRefCount
 	friend class LLTexUnit;
 public:
 
-    // For OS X use only -- get an estimate of how many bytes have been allocated in vram for textures
+    // Get an estimate of how many bytes have been allocated in vram for textures.
+    // Does not include mipmaps.
+    // NOTE: multiplying this number by two gives a good estimate for total
+    // video memory usage based on testing in lagland against an NVIDIA GPU.
     static U64 getTextureBytesAllocated();
 
 	// These 2 functions replace glGenTextures() and glDeleteTextures()
diff --git a/indra/llwindow/llwindowwin32.cpp b/indra/llwindow/llwindowwin32.cpp
index 20443988ab..656439e71e 100644
--- a/indra/llwindow/llwindowwin32.cpp
+++ b/indra/llwindow/llwindowwin32.cpp
@@ -414,6 +414,7 @@ struct LLWindowWin32::LLWindowWin32Thread : public LL::ThreadPool
     HWND mWindowHandle = NULL;
     HDC mhDC = 0;
 
+    // best guess at available video memory in MB
     std::atomic<U32> mAvailableVRAM;
 
     IDXGIAdapter3* mDXGIAdapter = nullptr;
@@ -4644,44 +4645,68 @@ void LLWindowWin32::LLWindowWin32Thread::updateVRAMUsage()
     LL_PROFILE_ZONE_SCOPED;
     if (mDXGIAdapter != nullptr)
     {
+        // NOTE: what lies below is hand wavy math based on compatibility testing and observation against a variety of hardware
+        //  It doesn't make sense, but please don't refactor it to make sense. -- davep
+
         DXGI_QUERY_VIDEO_MEMORY_INFO info;
         mDXGIAdapter->QueryVideoMemoryInfo(0, DXGI_MEMORY_SEGMENT_GROUP_LOCAL, &info);
 
-        // try to use no more than the available reserve minus 10%
-        U32 target = info.Budget / 1024 / 1024;
+#if 0 // debug 0 budget and 0 CU
+        info.Budget = 0;
+        info.CurrentUsage = 0;
+#endif
+
+        U32 budget_mb = info.Budget / 1024 / 1024;
+        U32 afr_mb = info.AvailableForReservation / 1024 / 1024;
+        // correct for systems that misreport budget
+        if (budget_mb == 0)
+        { 
+            // fall back to available for reservation clamped between 512MB and 2GB
+            budget_mb = llclamp(afr_mb, (U32) 512, (U32) 2048);
+        }
+
+        U32 cu_mb = info.CurrentUsage / 1024 / 1024;
+
+        // get an estimated usage based on texture bytes allocated
+        U32 eu_mb = LLImageGL::getTextureBytesAllocated() * 2 / 1024 / 1024;
 
-        // EXPERIMENTAL
-        // Trying to zero in on a good target usage, code here should be tuned against observed behavior
-        // of various hardware.
-        if (target > 4096)  // if 4GB are installed, try to leave 2GB free 
+        if (cu_mb == 0)
+        { // current usage is sometimes unreliable on Intel GPUs, fall back to estimated usage
+            cu_mb = llmax((U32)1, eu_mb);
+        }
+        F32 eu_error = (F32)((S32)eu_mb - (S32)cu_mb) / (F32)cu_mb;
+
+        U32 target_mb = info.Budget / 1024 / 1024;
+
+        if (target_mb > 4096)  // if 4GB are installed, try to leave 2GB free 
         {
-            target -= 2048;
+            target_mb -= 2048;
         }
         else // if less than 4GB are installed, try not to use more than half of it
         {
-            target /= 2;
+            target_mb /= 2;
         }
 
-        U32 used_vram = info.CurrentUsage / 1024 / 1024;
-
-        mAvailableVRAM = used_vram < target ? target - used_vram : 0;
+        mAvailableVRAM = cu_mb < target_mb ? target_mb - cu_mb : 0;
 
         LL_INFOS("Window") << "\nLocal\nAFR: " << info.AvailableForReservation / 1024 / 1024
             << "\nBudget: " << info.Budget / 1024 / 1024
             << "\nCR: " << info.CurrentReservation / 1024 / 1024
-            << "\nCU: " << info.CurrentUsage / 1024 / 1024 << LL_ENDL;
+            << "\nCU: " << info.CurrentUsage / 1024 / 1024
+            << "\nEU: " << eu_mb << llformat(" (%.2f)", eu_error)
+            << "\nTU: " << target_mb
+            << "\nAM: " << mAvailableVRAM << LL_ENDL;
 
-        mDXGIAdapter->QueryVideoMemoryInfo(0, DXGI_MEMORY_SEGMENT_GROUP_NON_LOCAL, &info);
+        /*mDXGIAdapter->QueryVideoMemoryInfo(0, DXGI_MEMORY_SEGMENT_GROUP_NON_LOCAL, &info);
         LL_INFOS("Window") << "\nNon-Local\nAFR: " << info.AvailableForReservation / 1024 / 1024
             << "\nBudget: " << info.Budget / 1024 / 1024
             << "\nCR: " << info.CurrentReservation / 1024 / 1024
-            << "\nCU: " << info.CurrentUsage / 1024 / 1024 << LL_ENDL;
+            << "\nCU: " << info.CurrentUsage / 1024 / 1024 << LL_ENDL;*/
     }
     else if (mD3DDevice != NULL)
     { // fallback to D3D9
         mAvailableVRAM = mD3DDevice->GetAvailableTextureMem() / 1024 / 1024;
     }
-
 }
 
 void LLWindowWin32::LLWindowWin32Thread::run()