added getTotalSystemMemory() function

include/mitsuba/core/util.h

@@ -114,6 +114,9 @@ extern MTS_EXPORT_CORE std::string getHostName();
 /// Return the process private memory usage in bytes
 extern MTS_EXPORT_CORE size_t getPrivateMemoryUsage();
 
+/// Returns the total amount of memory available to the OS
+extern MTS_EXPORT_CORE size_t getTotalSystemMemory();
+
 /// Return the fully qualified domain name of this machine
 extern MTS_EXPORT_CORE std::string getFQDN();
 

src/libcore/util.cpp

@@ -159,6 +159,19 @@ int getCoreCount() {
 #endif
 }
 
+size_t getTotalSystemMemory() {
+#if defined(__WINDOWS__)
+	MEMORYSTATUSEX status;
+	status.dwLength = sizeof(status);
+	GlobalMemoryStatusEx(&status);
+	return (size_t) status.ullTotalPhys;
+#else
+	size_t pages = sysconf(_SC_PHYS_PAGES);
+	size_t page_size = sysconf(_SC_PAGE_SIZE);
+	return pages * page_size;
+#endif
+}
+
 size_t getPrivateMemoryUsage() {
 #if defined(__WINDOWS__)
 	PROCESS_MEMORY_COUNTERS_EX pmc;

src/libpython/core.cpp

@@ -2079,6 +2079,7 @@ void export_core() {
 	bp::def("getCoreCount", &getCoreCount);
 	bp::def("getHostName", &getHostName);
 	bp::def("getPrivateMemoryUsage", &getPrivateMemoryUsage);
+	bp::def("getTotalSystemMemory", &getTotalSystemMemory);
 	bp::def("getFQDN", &getFQDN);
 	bp::def("rdtsc", &rdtsc);
 	bp::def("hypot2", &hypot2);