diff --git a/Common/Common.vcxproj b/Common/Common.vcxproj
index 7e61f89776..e0d85faeaf 100644
--- a/Common/Common.vcxproj
+++ b/Common/Common.vcxproj
@@ -529,6 +529,7 @@
     <ClInclude Include="System\Display.h" />
     <ClInclude Include="System\NativeApp.h" />
     <ClInclude Include="System\System.h" />
+    <ClInclude Include="Thread\Barrier.h" />
     <ClInclude Include="Thread\Channel.h" />
     <ClInclude Include="Thread\Event.h" />
     <ClInclude Include="Thread\ParallelLoop.h" />
diff --git a/Common/Common.vcxproj.filters b/Common/Common.vcxproj.filters
index 65b6eaccab..d701c1d1c6 100644
--- a/Common/Common.vcxproj.filters
+++ b/Common/Common.vcxproj.filters
@@ -415,6 +415,9 @@
     <ClInclude Include="GPU\Vulkan\VulkanProfiler.h">
       <Filter>GPU\Vulkan</Filter>
     </ClInclude>
+    <ClInclude Include="Thread\Barrier.h">
+      <Filter>Thread</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="ABI.cpp" />
diff --git a/Common/Thread/Barrier.h b/Common/Thread/Barrier.h
new file mode 100644
index 0000000000..11e55cdb00
--- /dev/null
+++ b/Common/Thread/Barrier.h
@@ -0,0 +1,31 @@
+#pragma once
+
+#include <condition_variable>
+#include <mutex>
+
+// Similar to C++20's std::barrier
+class CountingBarrier {
+public:
+	CountingBarrier(size_t count) : threadCount_(count) {}
+
+	void Arrive() {
+		std::unique_lock<std::mutex> lk(m);
+		counter++;
+		waiting++;
+		cv.wait(lk, [&] {return counter >= threadCount_; });
+		cv.notify_one();
+		waiting--;
+		if (waiting == 0) {
+			// Reset so it can be re-used.
+			counter = 0;
+		}
+		lk.unlock();
+	}
+
+private:
+	std::mutex m;
+	std::condition_variable cv;
+	size_t counter = 0;
+	size_t waiting = 0;
+	size_t threadCount_;
+};
diff --git a/unittest/TestThreadManager.cpp b/unittest/TestThreadManager.cpp
index 3445a33083..6c0abb90b5 100644
--- a/unittest/TestThreadManager.cpp
+++ b/unittest/TestThreadManager.cpp
@@ -1,11 +1,14 @@
 #include "Common/Log.h"
 #include "Common/TimeUtil.h"
+#include "Common/Thread/Barrier.h"
 #include "Common/Thread/ThreadManager.h"
 #include "Common/Thread/Channel.h"
 #include "Common/Thread/Promise.h"
 #include "Common/Thread/ParallelLoop.h"
 #include "Common/Thread/ThreadUtil.h"
 
+#include "UnitTest.h"
+
 struct ResultObject {
 	bool ok;
 };
@@ -56,16 +59,70 @@ bool TestParallelLoop(ThreadManager *threadMan) {
 	return true;
 }
 
+// This is some ugly stuff but realistic.
+const size_t THREAD_COUNT = 6;  // Must match the number of threads in TestMultithreadedScheduling
+const size_t ITERATIONS = 100000;
+
+static std::atomic<int> g_atomicCounter;
+static ThreadManager *g_threadMan;
+static CountingBarrier g_barrier(THREAD_COUNT + 1);
+
+class IncrementTask : public Task {
+public:
+	IncrementTask(TaskType type) : type_(type) {}
+	~IncrementTask() {}
+	virtual TaskType Type() const { return type_; }
+	virtual void Run() {
+		g_atomicCounter++;
+	}
+private:
+	TaskType type_;
+};
+
+void ThreadFunc() {
+	for (int i = 0; i < ITERATIONS; i++) {
+		g_threadMan->EnqueueTask(new IncrementTask((i & 1) ? TaskType::CPU_COMPUTE : TaskType::IO_BLOCKING));
+	}
+	g_barrier.Arrive();
+}
+
+bool TestMultithreadedScheduling() {
+	g_atomicCounter = 0;
+	std::thread thread1(ThreadFunc);
+	std::thread thread2(ThreadFunc);
+	std::thread thread3(ThreadFunc);
+	std::thread thread4(ThreadFunc);
+	std::thread thread5(ThreadFunc);
+	std::thread thread6(ThreadFunc);
+
+	// Just testing the barrier
+	g_barrier.Arrive();
+	// OK, all are done.
+
+	EXPECT_EQ_INT(g_atomicCounter, THREAD_COUNT * ITERATIONS);
+
+	thread1.join();
+	thread2.join();
+	thread3.join();
+	thread4.join();
+	thread5.join();
+	thread6.join();
+
+	return true;
+}
+
 bool TestThreadManager() {
 	ThreadManager manager;
 	manager.Init(8, 1);
 
+	g_threadMan = &manager;
+
 	Promise<ResultObject *> *object(Promise<ResultObject *>::Spawn(&manager, &ResultProducer, TaskType::IO_BLOCKING));
 
 	if (!TestParallelLoop(&manager)) {
 		return false;
 	}
-	sleep_ms(1000);
+	sleep_ms(100);
 
 	ResultObject *result = object->BlockUntilReady();
 	if (result) {
@@ -78,5 +135,9 @@ bool TestThreadManager() {
 		return false;
 	}
 
+	if (!TestMultithreadedScheduling()) {
+		return false;
+	}
+
 	return true;
 }
diff --git a/unittest/UnitTest.h b/unittest/UnitTest.h
index e953925d39..2267a7a87f 100644
--- a/unittest/UnitTest.h
+++ b/unittest/UnitTest.h
@@ -2,7 +2,7 @@
 
 #define EXPECT_TRUE(a) if (!(a)) { printf("%s:%i: Test Fail\n", __FUNCTION__, __LINE__); return false; }
 #define EXPECT_FALSE(a) if ((a)) { printf("%s:%i: Test Fail\n", __FUNCTION__, __LINE__); return false; }
-#define EXPECT_EQ_INT(a, b) if ((a) != (b)) { printf("%s:%i: Test Fail\n%d\nvs\n%d\n", __FUNCTION__, __LINE__, a, b); return false; }
+#define EXPECT_EQ_INT(a, b) if ((a) != (b)) { printf("%s:%i: Test Fail\n%d\nvs\n%d\n", __FUNCTION__, __LINE__, (int)(a), (int)(b)); return false; }
 #define EXPECT_EQ_HEX(a, b) if ((a) != (b)) { printf("%s:%i: Test Fail\n%x\nvs\n%x\n", __FUNCTION__, __LINE__, a, b); return false; }
 #define EXPECT_EQ_FLOAT(a, b) if ((a) != (b)) { printf("%s:%i: Test Fail\n%f\nvs\n%f\n", __FUNCTION__, __LINE__, a, b); return false; }
 #define EXPECT_APPROX_EQ_FLOAT(a, b) if (fabsf((a)-(b))>0.00001f) { printf("%s:%i: Test Fail\n%f\nvs\n%f\n", __FUNCTION__, __LINE__, a, b); /*return false;*/ }