diff --git a/uppsrc/Core/Cpu.cpp b/uppsrc/Core/Cpu.cpp
index 35a11b101..fadbc8a6f 100644
--- a/uppsrc/Core/Cpu.cpp
+++ b/uppsrc/Core/Cpu.cpp
@@ -129,24 +129,29 @@ int CPU_Cores()
 
 #endif
 
-void GetSystemMemoryStatus(uint64& total, uint64& free)
+#ifdef PLATFORM_MACOS
+#include <mach/mach.h>
+#include <mach/vm_statistics.h>
+#endif
+
+void GetSystemMemoryStatus(uint64& total, uint64& available)
 {
 #ifdef PLATFORM_WIN32
 	MEMORYSTATUSEX m;
 	m.dwLength = sizeof(m);
 	if(GlobalMemoryStatusEx(&m)) {
 		total = m.ullTotalPhys;
-		free = m.ullAvailPhys;
+		available = m.ullAvailPhys;
 		return;
 	}
 #endif
 #ifdef PLATFORM_LINUX
 	int pgsz = getpagesize();
 	total = sysconf(_SC_PHYS_PAGES);
-	free = sysconf(_SC_AVPHYS_PAGES);
-	if(total >= 0 && free >= 0) {
+	available = sysconf(_SC_AVPHYS_PAGES);
+	if(total >= 0 && available >= 0) {
 		total *= pgsz;
-		free *= pgsz;
+		available *= pgsz;
 		return;
 	}
 #endif
@@ -160,13 +165,35 @@ void GetSystemMemoryStatus(uint64& total, uint64& free)
 
     if(sysctlbyname("vm.vmtotal", &vmt, &vmt_size, NULL, 0) >= 0 &&
        sysctlbyname("vm.stats.vm.v_page_size", &page_size, &uint_size, NULL, 0) >= 0) {
-		free = vmt.t_free * page_size;
+		available = vmt.t_free * page_size;
 		total = vmt.t_avm * page_size;
 		return;
     }
+#endif
+#ifdef PLATFORM_MACOS
+	mach_msg_type_number_t count = HOST_VM_INFO_COUNT;
+	vm_statistics_data_t vmstat;
+
+    int mib[2];
+    int64 physical_memory;
+    size_t length;
+
+    // Get the Physical memory size
+    mib[0] = CTL_HW;
+    mib[1] = HW_MEMSIZE;
+    length = sizeof(int64);
+
+	if(host_statistics(mach_host_self(), HOST_VM_INFO, (host_info_t)&vmstat, &count) == KERN_SUCCESS &&
+	   sysctl(mib, 2, &physical_memory, &length, NULL, 0) >= 0) {
+		int pgsz = getpagesize();
+		available = (vmstat.free_count + vmstat.inactive_count) * pgsz;
+//		available = physical_memory - (vmstat.wire_count + vmstat.inactive_count) * pgsz;
+		total = physical_memory;
+		return;
+	}
 #endif
 	total = 256*1024*1024;
-	free = 16*1024*1024;
+	available = 16*1024*1024;
 }
 
 #define ENDIAN_SWAP { while(count--) { EndianSwap(*v++); } }
diff --git a/uppsrc/Core/Defs.h b/uppsrc/Core/Defs.h
index 1aabe1d76..f7f43032f 100644
--- a/uppsrc/Core/Defs.h
+++ b/uppsrc/Core/Defs.h
@@ -484,7 +484,7 @@ bool CpuAVX();
 
 int  CPU_Cores();
 
-void GetSystemMemoryStatus(uint64& total, uint64& free);
+void GetSystemMemoryStatus(uint64& total, uint64& available);
 
 template <class T>
 inline void Swap(T& a, T& b) { T tmp = pick(a); a = pick(b); b = pick(tmp); }