--- a/src/os/macosx/macos.mm
+++ b/src/os/macosx/macos.mm
@@ -172,3 +172,20 @@
 	return true;
 }
 #endif
+
+uint GetCPUCoreCount()
+{
+	uint count = 1;
+#if (MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5)
+	if (MacOSVersionIsAtLeast(10, 5, 0)) {
+		count = [ [ NSProcessInfo processInfo ] activeProcessorCount ];
+	} else
+#endif
+	{
+#if (MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_5)
+		count = MPProcessorsScheduled();
+#endif
+	}
+
+	return count;
+}

--- a/src/os/os2/os2.cpp
+++ b/src/os/os2/os2.cpp
@@ -210,3 +210,8 @@
 
 const char *FS2OTTD(const char *name) {return name;}
 const char *OTTD2FS(const char *name) {return name;}
+
+uint GetCPUCoreCount()
+{
+	return 1;
+}

--- a/src/os/unix/unix.cpp
+++ b/src/os/unix/unix.cpp
@@ -28,10 +28,18 @@
 	#define HAS_STATVFS
 #endif
 
+#if defined(OPENBSD) || defined(__NetBSD__) || defined(__FreeBSD__)
+	#define HAS_SYSCTL
+#endif
+
 #ifdef HAS_STATVFS
 #include <sys/statvfs.h>
 #endif
 
+#ifdef HAS_SYSCTL
+#include <sys/sysctl.h>
+#endif
+
 
 #ifdef __MORPHOS__
 #include <exec/types.h>
@@ -318,3 +326,26 @@
 		usleep(milliseconds * 1000);
 	#endif
 }
+
+
+#ifndef __APPLE__
+uint GetCPUCoreCount()
+{
+	uint count = 1;
+#ifdef HAS_SYSCTL
+	int ncpu = 0;
+	size_t len = sizeof(ncpu);
+
+	if (sysctlbyname("hw.availcpu", &ncpu, &len, NULL, 0) < 0) {
+		sysctlbyname("hw.ncpu", &ncpu, &len, NULL, 0);
+	}
+
+	if (ncpu > 0) count = ncpu;
+#elif defined(_SC_NPROCESSORS_ONLN)
+	long res = sysconf(_SC_NPROCESSORS_ONLN);
+	if (res > 0) count = res;
+#endif
+
+	return count;
+}
+#endif

--- a/src/os/windows/win32.cpp
+++ b/src/os/windows/win32.cpp
@@ -753,3 +753,11 @@
 	static char retbuf[6] = {lang[0], lang[1], '_', country[0], country[1], 0};
 	return retbuf;
 }
+
+uint GetCPUCoreCount()
+{
+	SYSTEM_INFO info;
+
+	GetSystemInfo(&info);
+	return info.dwNumberOfProcessors;
+}

--- a/src/thread/thread.h
+++ b/src/thread/thread.h
@@ -88,4 +88,10 @@
 	virtual void SendSignal() = 0;
 };
 
+/**
+ * Get number of processor cores in the system, including HyperThreading or similar.
+ * @return Total number of processor cores.
+ */
+uint GetCPUCoreCount();
+
 #endif /* THREAD_H */