diff --git a/Core/Config.cpp b/Core/Config.cpp
index c2162ddece..73ed515c97 100644
--- a/Core/Config.cpp
+++ b/Core/Config.cpp
@@ -75,6 +75,7 @@ void Config::Load(const char *iniFileName, const char *controllerIniFilename) {
 	general->Get("EnableCheats", &bEnableCheats, false);
 	general->Get("ScreenshotsAsPNG", &bScreenshotsAsPNG, false);
 	general->Get("StateSlot", &iCurrentStateSlot, 0);
+	general->Get("RewindFlipFrequency", &iRewindFlipFrequency, 0);
 	general->Get("GridView1", &bGridView1, true);
 	general->Get("GridView2", &bGridView2, true);
 	general->Get("GridView3", &bGridView3, true);
@@ -341,6 +342,7 @@ void Config::Save() {
 		general->Set("EnableCheats", bEnableCheats);
 		general->Set("ScreenshotsAsPNG", bScreenshotsAsPNG);
 		general->Set("StateSlot", iCurrentStateSlot);
+		general->Set("RewindFlipFrequency", iRewindFlipFrequency);
 		general->Set("GridView1", bGridView1);
 		general->Set("GridView2", bGridView2);
 		general->Set("GridView3", bGridView3);
diff --git a/Core/Config.h b/Core/Config.h
index 7358ee7076..d28168d366 100644
--- a/Core/Config.h
+++ b/Core/Config.h
@@ -92,6 +92,7 @@ public:
 	int iForceMaxEmulatedFPS;
 	int iMaxRecent;
 	int iCurrentStateSlot;
+	int iRewindFlipFrequency;
 	bool bEnableCheats;
 	bool bReloadCheats;
 	bool bDisableStencilTest;
diff --git a/Core/HLE/sceKernelThread.cpp b/Core/HLE/sceKernelThread.cpp
index d0278a7f57..b475dcbf55 100644
--- a/Core/HLE/sceKernelThread.cpp
+++ b/Core/HLE/sceKernelThread.cpp
@@ -520,7 +520,7 @@ public:
 
 	virtual void DoState(PointerWrap &p)
 	{
-		auto s = p.Section("Thread", 1);
+		auto s = p.Section("Thread", 1, 2);
 		if (!s)
 			return;
 
@@ -537,6 +537,12 @@ public:
 		p.Do(pendingMipsCalls);
 		p.Do(pushedStacks);
 		p.Do(currentStack);
+
+		if (s >= 2)
+		{
+			p.Do(waitingThreads);
+			p.Do(pausedWaits);
+		}
 	}
 
 	NativeThread nt;
diff --git a/Core/SaveState.cpp b/Core/SaveState.cpp
index 0f71933c16..4cb48e7d65 100644
--- a/Core/SaveState.cpp
+++ b/Core/SaveState.cpp
@@ -75,7 +75,7 @@ namespace SaveState
 		CChunkFileReader::Error Save()
 		{
 			int n = next_++ % size_;
-			if (n == first_)
+			if ((next_ % size_) == first_)
 				++first_;
 
 			SaveStart state;
@@ -89,7 +89,7 @@ namespace SaveState
 		CChunkFileReader::Error Restore()
 		{
 			// No valid states left.
-			if (next_ == first_)
+			if (Empty())
 				return CChunkFileReader::ERROR_BAD_FILE;
 
 			int n = (next_-- + size_) % size_;
@@ -100,6 +100,17 @@ namespace SaveState
 			return CChunkFileReader::LoadPtr(&states_[n][0], state);
 		}
 
+		void Clear()
+		{
+			first_ = 0;
+			next_ = 0;
+		}
+
+		bool Empty()
+		{
+			return next_ == first_;
+		}
+
 		typedef std::vector<u8> StateBuffer;
 		int first_;
 		int next_;
@@ -114,8 +125,6 @@ namespace SaveState
 	// TODO: Should this be configurable?
 	static const int REWIND_NUM_STATES = 5;
 	static StateRingbuffer rewindStates(REWIND_NUM_STATES);
-	// TODO: g_Config setting or something instead.
-	static int rewindStateFreq = 0;
 	// TODO: Any reason for this to be configurable?
 	const static float rewindMaxWallFrequency = 1.0f;
 	static float rewindLastTime = 0.0f;
@@ -179,6 +188,11 @@ namespace SaveState
 		Enqueue(Operation(SAVESTATE_REWIND, std::string(""), callback, cbUserData));
 	}
 
+	bool CanRewind()
+	{
+		return !rewindStates.Empty();
+	}
+
 
 	// Slot utilities
 
@@ -302,7 +316,7 @@ namespace SaveState
 
 	static inline void CheckRewindState()
 	{
-		if (gpuStats.numFlips % rewindStateFreq != 0)
+		if (gpuStats.numFlips % g_Config.iRewindFlipFrequency != 0)
 			return;
 
 		// For fast-forwarding, otherwise they may be useless and too close.
@@ -317,7 +331,7 @@ namespace SaveState
 
 	void Process()
 	{
-		if (rewindStateFreq != 0)
+		if (g_Config.iRewindFlipFrequency != 0 && gpuStats.numFlips != 0)
 			CheckRewindState();
 
 		if (!needsProcess)
@@ -429,5 +443,6 @@ namespace SaveState
 		pspFileSystem.MkDir("ms0:/PSP/PPSSPP_STATE");
 
 		std::lock_guard<std::recursive_mutex> guard(mutex);
+		rewindStates.Clear();
 	}
 }
diff --git a/Core/SaveState.h b/Core/SaveState.h
index b2b9fda16d..65eccdb9ae 100644
--- a/Core/SaveState.h
+++ b/Core/SaveState.h
@@ -52,6 +52,9 @@ namespace SaveState
 	// Warning: callback will be called on a different thread.
 	void Rewind(Callback callback = 0, void *cbUserData = 0);
 
+	// Returns true if there are rewind snapshots available.
+	bool CanRewind();
+
 	// Check if there's any save stating needing to be done.  Normally called once per frame.
 	void Process();
 };
diff --git a/UI/GameSettingsScreen.cpp b/UI/GameSettingsScreen.cpp
index dc2ec89e63..b903fba78a 100644
--- a/UI/GameSettingsScreen.cpp
+++ b/UI/GameSettingsScreen.cpp
@@ -254,6 +254,7 @@ void GameSettingsScreen::CreateViews() {
 	systemSettings->Add(new CheckBox(&g_Config.bSeparateIOThread, s->T("I/O on thread (experimental)")))->SetEnabled(!PSP_IsInited());
 #endif
 	systemSettings->Add(new PopupSliderChoice(&g_Config.iLockedCPUSpeed, 0, 1000, s->T("Change CPU Clock", "Change CPU Clock (0 = default)"), screenManager()));
+	systemSettings->Add(new PopupSliderChoice(&g_Config.iRewindFlipFrequency, 0, 1800, s->T("Rewind Snapshot Frequency (0 = off, mem hog)"), screenManager()));
 
 	systemSettings->Add(new CheckBox(&g_Config.bAtomicAudioLocks, s->T("Atomic Audio locks (experimental)")))->SetEnabled(!PSP_IsInited());
 
diff --git a/UI/MainScreen.cpp b/UI/MainScreen.cpp
index 4c11c98f4e..a13864e470 100644
--- a/UI/MainScreen.cpp
+++ b/UI/MainScreen.cpp
@@ -779,6 +779,12 @@ void GamePauseScreen::CreateViews() {
 	loadStateButton_ = leftColumnItems->Add(new Choice(i->T("Load State")));
 	loadStateButton_->OnClick.Handle(this, &GamePauseScreen::OnLoadState);
 
+	if (g_Config.iRewindFlipFrequency > 0) {
+		UI::Choice *rewindButton = leftColumnItems->Add(new Choice(i->T("Rewind")));
+		rewindButton->SetEnabled(SaveState::CanRewind());
+		rewindButton->OnClick.Handle(this, &GamePauseScreen::OnRewind);
+	}
+
 	ViewGroup *rightColumn = new ScrollView(ORIENT_VERTICAL, new LinearLayoutParams(300, FILL_PARENT, actionMenuMargins));
 	root_->Add(rightColumn);
 
@@ -833,6 +839,14 @@ UI::EventReturn GamePauseScreen::OnSaveState(UI::EventParams &e) {
 	screenManager()->finishDialog(this, DR_CANCEL);
 	return UI::EVENT_DONE;
 }
+
+UI::EventReturn GamePauseScreen::OnRewind(UI::EventParams &e) {
+	SaveState::Rewind(0, 0);
+
+	screenManager()->finishDialog(this, DR_CANCEL);
+	return UI::EVENT_DONE;
+}
+
 UI::EventReturn GamePauseScreen::OnCwCheat(UI::EventParams &e) {
 	screenManager()->push(new CwCheatScreen());
 	return UI::EVENT_DONE;
diff --git a/UI/MainScreen.h b/UI/MainScreen.h
index bdac77ca83..4bdcdb9065 100644
--- a/UI/MainScreen.h
+++ b/UI/MainScreen.h
@@ -72,6 +72,7 @@ private:
 
 	UI::EventReturn OnSaveState(UI::EventParams &e);
 	UI::EventReturn OnLoadState(UI::EventParams &e);
+	UI::EventReturn OnRewind(UI::EventParams &e);
 
 	UI::EventReturn OnStateSelected(UI::EventParams &e);
 	UI::EventReturn OnCwCheat(UI::EventParams &e);