Set realtime thread priority for engine and engine worker threads.

include/system.hpp

@@ -16,6 +16,7 @@ void createDirectory(const std::string &path);
 /** Currently this lies and returns the number of logical cores instead. */
 int getPhysicalCoreCount();
 void setThreadName(const std::string &name);
+void setThreadRealTime();
 
 /** Opens a URL, also happens to work with PDFs and folders.
 Shell injection is possible, so make sure the URL is trusted or hard coded.

src/engine/Engine.cpp

@@ -101,6 +101,7 @@ struct EngineWorker {
 	void start() {
 		thread = std::thread([&] {
 			system::setThreadName("Engine worker");
+			system::setThreadRealTime();
 			run();
 		});
 	}
@@ -298,10 +299,10 @@ static void Engine_step(Engine *engine) {
 }
 
 static void Engine_run(Engine *engine) {
-#if defined ARCH_LIN
-	// Name thread
+	// Set up thread
 	system::setThreadName("Engine");
-#endif
+	system::setThreadRealTime();
+
 	// Set CPU to flush-to-zero (FTZ) and denormals-are-zero (DAZ) mode
 	// https://software.intel.com/en-us/node/682949
 	_MM_SET_FLUSH_ZERO_MODE(_MM_FLUSH_ZERO_ON);

src/system.cpp

@@ -3,9 +3,15 @@
 #include <dirent.h>
 #include <sys/stat.h>
 
+#if defined ARCH_LIN
+	#include <pthread.h>
+	#include <sched.h>
+#endif
+
 #if defined ARCH_WIN
 	#include <windows.h>
 	#include <shellapi.h>
+	#include <processthreadsapi.h>
 #endif
 
 
@@ -84,8 +90,23 @@ int getPhysicalCoreCount() {
 }
 
 void setThreadName(const std::string &name) {
-#if defined ARCH_LIN
+#if defined ARCH_LIN || defined ARCH_MAC
 	pthread_setname_np(pthread_self(), name.c_str());
+#elif defined ARCH_WIN
+	SetThreadDescription(GetCurrentThread(), name.c_str());
+#endif
+}
+
+void setThreadRealTime() {
+#if defined ARCH_LIN || defined ARCH_MAC
+	int policy = SCHED_RR;
+	struct sched_param param;
+	param.sched_priority = sched_get_priority_max(policy);
+	pthread_setschedparam(pthread_self(), policy, &param);
+#elif defined ARCH_WIN
+	// Set entire process as realtime
+	SetPriorityClass(GetCurrentProcess(), HIGH_PRIORITY_CLASS);
+	SetThreadPriority(GetCurrentThread(), THREAD_PRIORITY_TIME_CRITICAL);
 #endif
 }