diff --git a/src/gl/utility/gl_clock.cpp b/src/gl/utility/gl_clock.cpp
index 68a2b06e5..2377029c2 100644
--- a/src/gl/utility/gl_clock.cpp
+++ b/src/gl/utility/gl_clock.cpp
@@ -40,6 +40,8 @@
 #include <intrin.h>
 
 #define USE_WINDOWS_DWORD
+#elif defined __APPLE__
+#include <sys/sysctl.h>
 #endif
 
 #include "i_system.h"
@@ -114,6 +116,15 @@ void gl_CalculateCPUSpeed ()
 			gl_SecondsPerCycle = 1.0 / CyclesPerSecond;
 			gl_MillisecPerCycle = 1000.0 / CyclesPerSecond;
 		}
+	#elif defined __APPLE__
+		long long frequency;
+		size_t size = sizeof frequency;
+
+		if (0 == sysctlbyname("machdep.tsc.frequency", &frequency, &size, nullptr, 0) && 0 != frequency)
+		{
+			gl_SecondsPerCycle = 1.0 / frequency;
+			gl_MillisecPerCycle = 1000.0 / frequency;
+		}
 	#endif
 }
 
diff --git a/src/gl/utility/gl_clock.h b/src/gl/utility/gl_clock.h
index 4d5163d86..2ccda639a 100644
--- a/src/gl/utility/gl_clock.h
+++ b/src/gl/utility/gl_clock.h
@@ -7,11 +7,11 @@
 
 extern bool gl_benching;
 
-#ifdef _MSC_VER
-
 extern double gl_SecondsPerCycle;
 extern double gl_MillisecPerCycle;
 
+#ifdef _MSC_VER
+
 __forceinline long long GetClockCycle ()
 {
 #if _M_X64
@@ -21,10 +21,14 @@ __forceinline long long GetClockCycle ()
 #endif
 }
 
-#elif defined(__GNUG__) && defined(__i386__)
+#elif defined __APPLE__ && (defined __i386__ || defined __x86_64__)
 
-extern double gl_SecondsPerCycle;
-extern double gl_MillisecPerCycle;
+inline long long GetClockCycle()
+{
+	return __builtin_ia32_rdtsc();
+}
+
+#elif defined(__GNUG__) && defined(__i386__)
 
 inline long long GetClockCycle()
 {
@@ -42,21 +46,12 @@ inline long long GetClockCycle()
 
 #else
 
-extern double gl_SecondsPerCycle;
-extern double gl_MillisecPerCycle;
-
 inline long long GetClockCycle ()
 {
 	return 0;
 }
 #endif
 
-#if defined (__APPLE__)
-
-typedef cycle_t glcycle_t;
-
-#else // !__APPLE__
-
 class glcycle_t
 {
 public:
@@ -100,8 +95,6 @@ private:
 	long long Counter;
 };
 
-#endif // __APPLE__
-
 extern glcycle_t RenderWall,SetupWall,ClipWall;
 extern glcycle_t RenderFlat,SetupFlat;
 extern glcycle_t RenderSprite,SetupSprite;
@@ -122,4 +115,4 @@ void CheckBench();
 void  checkBenchActive();
 
 
-#endif
\ No newline at end of file
+#endif
diff --git a/src/posix/cocoa/i_video.mm b/src/posix/cocoa/i_video.mm
index 2ee7458a8..637ca0d7f 100644
--- a/src/posix/cocoa/i_video.mm
+++ b/src/posix/cocoa/i_video.mm
@@ -534,6 +534,9 @@ CocoaVideo::CocoaVideo()
 {
 	memset(&m_modeIterator, 0, sizeof m_modeIterator);
 
+	extern void gl_CalculateCPUSpeed();
+	gl_CalculateCPUSpeed();
+
 	// Create OpenGL pixel format
 
 	NSOpenGLPixelFormat* pixelFormat = CreatePixelFormat(OpenGLProfile::Core);