[host] general performance improvements

host/main.cpp

@@ -19,6 +19,7 @@ Place, Suite 330, Boston, MA 02111-1307 USA
 
 #include <windows.h>
 #include <shlwapi.h>
+#include <avrt.h>
 
 #include "common/debug.h"
 #include "vendor/getopt/getopt.h"
@@ -41,6 +42,8 @@ void doLicense();
 bool consoleActive = false;
 void setupConsole();
 
+extern "C" NTSYSAPI NTSTATUS NTAPI NtSetTimerResolution(ULONG DesiredResolution, BOOLEAN SetResolution, PULONG CurrentResolution);
+
 struct StartupArgs
 {
   bool foreground;
@@ -54,8 +57,6 @@ int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdParam
   TraceUtil::Initialize();
   CoInitializeEx(NULL, COINIT_APARTMENTTHREADED | COINIT_DISABLE_OLE1DDE);
 
-  SetPriorityClass(GetCurrentProcess(), REALTIME_PRIORITY_CLASS);
-
   struct StartupArgs args;
   args.foreground = false;
   args.captureDevice = NULL;
@@ -89,6 +90,19 @@ int run(struct StartupArgs & args)
   if (args.foreground)
     setupConsole();
 
+  /* increase the system timer resolution */
+  ULONG currentRes;
+  NtSetTimerResolution(0, TRUE, &currentRes);
+
+  /* boost our thread priority class as high as possible */
+  SetPriorityClass(GetCurrentProcess(), REALTIME_PRIORITY_CLASS);
+
+  /* use MMCSS to boost our priority for capture */
+  DWORD taskIndex = 0;
+  HANDLE task = AvSetMmThreadCharacteristics(L"Capture", &taskIndex);
+  if (!task || (AvSetMmThreadPriority(task, AVRT_PRIORITY_CRITICAL) == FALSE))
+    DEBUG_WARN("Failed to boosted priority using MMCSS");
+
   ICapture * captureDevice;
   if (args.captureDevice == NULL)
     captureDevice = CaptureFactory::DetectDevice(&args.captureOptions);
@@ -121,6 +135,10 @@ int run(struct StartupArgs & args)
   }
 
   svc->DeInitialize();
+
+  if (task)
+    AvRevertMmThreadCharacteristics(task);
+
   return 0;
 }