diff --git a/src/isomorphic/ReactDebugTool.js b/src/isomorphic/ReactDebugTool.js
index 005378b76d76c..f88513b387157 100644
--- a/src/isomorphic/ReactDebugTool.js
+++ b/src/isomorphic/ReactDebugTool.js
@@ -48,45 +48,54 @@ var currentTimerDebugID = null;
 var currentTimerStartTime = null;
 var currentTimerType = null;
 
+function clearHistory() {
+  ReactComponentTreeDevtool.purgeUnmountedComponents();
+  ReactNativeOperationHistoryDevtool.clearHistory();
+}
+
+function getTreeSnapshot(registeredIDs) {
+  return registeredIDs.reduce((tree, id) => {
+    var ownerID = ReactComponentTreeDevtool.getOwnerID(id);
+    var parentID = ReactComponentTreeDevtool.getParentID(id);
+    tree[id] = {
+      displayName: ReactComponentTreeDevtool.getDisplayName(id),
+      text: ReactComponentTreeDevtool.getText(id),
+      updateCount: ReactComponentTreeDevtool.getUpdateCount(id),
+      childIDs: ReactComponentTreeDevtool.getChildIDs(id),
+      // Text nodes don't have owners but this is close enough.
+      ownerID: ownerID || ReactComponentTreeDevtool.getOwnerID(parentID),
+      parentID,
+    };
+    return tree;
+  }, {});
+}
+
 function resetMeasurements() {
   if (__DEV__) {
+    var previousStartTime = currentFlushStartTime;
+    var previousMeasurements = currentFlushMeasurements || [];
+    var previousOperations = ReactNativeOperationHistoryDevtool.getHistory();
+
     if (!isProfiling || currentFlushNesting === 0) {
       currentFlushStartTime = null;
       currentFlushMeasurements = null;
+      clearHistory();
       return;
     }
 
-    var previousStartTime = currentFlushStartTime;
-    var previousMeasurements = currentFlushMeasurements || [];
-    var previousOperations = ReactNativeOperationHistoryDevtool.getHistory();
-
     if (previousMeasurements.length || previousOperations.length) {
       var registeredIDs = ReactComponentTreeDevtool.getRegisteredIDs();
       flushHistory.push({
         duration: performanceNow() - previousStartTime,
         measurements: previousMeasurements || [],
         operations: previousOperations || [],
-        treeSnapshot: registeredIDs.reduce((tree, id) => {
-          var ownerID = ReactComponentTreeDevtool.getOwnerID(id);
-          var parentID = ReactComponentTreeDevtool.getParentID(id);
-          tree[id] = {
-            displayName: ReactComponentTreeDevtool.getDisplayName(id),
-            text: ReactComponentTreeDevtool.getText(id),
-            updateCount: ReactComponentTreeDevtool.getUpdateCount(id),
-            childIDs: ReactComponentTreeDevtool.getChildIDs(id),
-            // Text nodes don't have owners but this is close enough.
-            ownerID: ownerID || ReactComponentTreeDevtool.getOwnerID(parentID),
-            parentID,
-          };
-          return tree;
-        }, {}),
+        treeSnapshot: getTreeSnapshot(registeredIDs),
       });
     }
 
+    clearHistory();
     currentFlushStartTime = performanceNow();
     currentFlushMeasurements = [];
-    ReactComponentTreeDevtool.purgeUnmountedComponents();
-    ReactNativeOperationHistoryDevtool.clearHistory();
   }
 }
 
diff --git a/src/isomorphic/__tests__/ReactPerf-test.js b/src/isomorphic/__tests__/ReactPerf-test.js
index c81a4e82a79d9..644bc618b849f 100644
--- a/src/isomorphic/__tests__/ReactPerf-test.js
+++ b/src/isomorphic/__tests__/ReactPerf-test.js
@@ -241,6 +241,21 @@ describe('ReactPerf', function() {
     });
   });
 
+  it('should include stats for components unmounted during measurement', function() {
+    var container = document.createElement('div');
+    var measurements = measure(() => {
+      ReactDOM.render(<Div><Div key="a" /></Div>, container);
+      ReactDOM.render(<Div><Div key="b" /></Div>, container);
+    });
+    expect(ReactPerf.getExclusive(measurements)).toEqual([{
+      key: 'Div',
+      instanceCount: 3,
+      counts: { ctor: 3, render: 4 },
+      durations: { ctor: 3, render: 4 },
+      totalDuration: 7,
+    }]);
+  });
+
   it('warns once when using getMeasurementsSummaryMap', function() {
     var measurements = measure(() => {});
     spyOn(console, 'error');
diff --git a/src/isomorphic/devtools/ReactComponentTreeDevtool.js b/src/isomorphic/devtools/ReactComponentTreeDevtool.js
index 57e85b39dfc3c..85902c30d09cc 100644
--- a/src/isomorphic/devtools/ReactComponentTreeDevtool.js
+++ b/src/isomorphic/devtools/ReactComponentTreeDevtool.js
@@ -106,6 +106,11 @@ var ReactComponentTreeDevtool = {
   },
 
   purgeUnmountedComponents() {
+    if (ReactComponentTreeDevtool._preventPurging) {
+      // Should only be used for testing.
+      return;
+    }
+
     Object.keys(tree)
       .filter(id => !tree[id].isMounted)
       .forEach(purgeDeep);
diff --git a/src/isomorphic/devtools/ReactNativeOperationHistoryDevtool.js b/src/isomorphic/devtools/ReactNativeOperationHistoryDevtool.js
index 50478cc405d6c..46b8194465db2 100644
--- a/src/isomorphic/devtools/ReactNativeOperationHistoryDevtool.js
+++ b/src/isomorphic/devtools/ReactNativeOperationHistoryDevtool.js
@@ -23,6 +23,11 @@ var ReactNativeOperationHistoryDevtool = {
   },
 
   clearHistory() {
+    if (ReactNativeOperationHistoryDevtool._preventClearing) {
+      // Should only be used for tests.
+      return;
+    }
+
     history = [];
   },
 
diff --git a/src/isomorphic/devtools/__tests__/ReactComponentTreeDevtool-test.js b/src/isomorphic/devtools/__tests__/ReactComponentTreeDevtool-test.js
index 106307d0d25ac..1c5cdb7049ab0 100644
--- a/src/isomorphic/devtools/__tests__/ReactComponentTreeDevtool-test.js
+++ b/src/isomorphic/devtools/__tests__/ReactComponentTreeDevtool-test.js
@@ -97,13 +97,20 @@ describe('ReactComponentTreeDevtool', () => {
     // Ensure the tree is correct on every step.
     pairs.forEach(([element, expectedTree]) => {
       currentElement = element;
+
+      // Mount a new tree or update the existing tree.
       ReactDOM.render(<Wrapper />, node);
       expect(getActualTree()).toEqual(expectedTree);
+
+      // Purging should have no effect
+      // on the tree we expect to see.
       ReactComponentTreeDevtool.purgeUnmountedComponents();
       expect(getActualTree()).toEqual(expectedTree);
     });
+
+    // Unmounting the root node should purge
+    // the whole subtree automatically.
     ReactDOM.unmountComponentAtNode(node);
-    ReactComponentTreeDevtool.purgeUnmountedComponents();
     expect(getActualTree()).toBe(undefined);
     expect(getRootDisplayNames()).toEqual([]);
     expect(getRegisteredDisplayNames()).toEqual([]);
@@ -112,8 +119,23 @@ describe('ReactComponentTreeDevtool', () => {
     // Ensure the tree is correct on every step.
     pairs.forEach(([element, expectedTree]) => {
       currentElement = element;
+
+      // Rendering to string should not produce any entries
+      // because ReactDebugTool purges it when the flush ends.
+      ReactDOMServer.renderToString(<Wrapper />);
+      expect(getActualTree()).toBe(undefined);
+      expect(getRootDisplayNames()).toEqual([]);
+      expect(getRegisteredDisplayNames()).toEqual([]);
+
+      // To test it, we tell the devtool to ignore next purge
+      // so the cleanup request by ReactDebugTool is ignored.
+      // This lets us make assertions on the actual tree.
+      ReactComponentTreeDevtool._preventPurging = true;
       ReactDOMServer.renderToString(<Wrapper />);
+      ReactComponentTreeDevtool._preventPurging = false;
       expect(getActualTree()).toEqual(expectedTree);
+
+      // Purge manually since we skipped the automatic purge.
       ReactComponentTreeDevtool.purgeUnmountedComponents();
       expect(getActualTree()).toBe(undefined);
       expect(getRootDisplayNames()).toEqual([]);
@@ -1631,7 +1653,7 @@ describe('ReactComponentTreeDevtool', () => {
     assertTreeMatches([element, tree], {includeOwnerDisplayName: true});
   });
 
-  it('preserves unmounted components until purge', () => {
+  it('purges unmounted components automatically', () => {
     var node = document.createElement('div');
     var renderBar = true;
     var fooInstance;
@@ -1666,31 +1688,15 @@ describe('ReactComponentTreeDevtool', () => {
     renderBar = false;
     ReactDOM.render(<Foo />, node);
     expect(
-      getTree(barInstance._debugID, {
-        includeParentDisplayName: true,
-        expectedParentID: fooInstance._debugID,
-      })
+      getTree(barInstance._debugID, {expectedParentID: null})
     ).toEqual({
-      displayName: 'Bar',
-      parentDisplayName: 'Foo',
+      displayName: 'Unknown',
       children: [],
     });
 
     ReactDOM.unmountComponentAtNode(node);
     expect(
-      getTree(barInstance._debugID, {
-        includeParentDisplayName: true,
-        expectedParentID: fooInstance._debugID,
-      })
-    ).toEqual({
-      displayName: 'Bar',
-      parentDisplayName: 'Foo',
-      children: [],
-    });
-
-    ReactComponentTreeDevtool.purgeUnmountedComponents();
-    expect(
-      getTree(barInstance._debugID, {includeParentDisplayName: true})
+      getTree(barInstance._debugID, {expectedParentID: null})
     ).toEqual({
       displayName: 'Unknown',
       children: [],
@@ -1719,7 +1725,7 @@ describe('ReactComponentTreeDevtool', () => {
 
     ReactDOM.unmountComponentAtNode(node);
     expect(ReactComponentTreeDevtool.getUpdateCount(divID)).toEqual(0);
-    expect(ReactComponentTreeDevtool.getUpdateCount(spanID)).toEqual(2);
+    expect(ReactComponentTreeDevtool.getUpdateCount(spanID)).toEqual(0);
   });
 
   it('does not report top-level wrapper as a root', () => {
@@ -1733,12 +1739,6 @@ describe('ReactComponentTreeDevtool', () => {
 
     ReactDOM.unmountComponentAtNode(node);
     expect(getRootDisplayNames()).toEqual([]);
-
-    ReactComponentTreeDevtool.purgeUnmountedComponents();
-    expect(getRootDisplayNames()).toEqual([]);
-
-    // This currently contains TopLevelWrapper until purge
-    // so we only check it at the very end.
     expect(getRegisteredDisplayNames()).toEqual([]);
   });
 });
diff --git a/src/isomorphic/devtools/__tests__/ReactComponentTreeDevtool-test.native.js b/src/isomorphic/devtools/__tests__/ReactComponentTreeDevtool-test.native.js
index 3113d6fcad898..f3b026b459ccf 100644
--- a/src/isomorphic/devtools/__tests__/ReactComponentTreeDevtool-test.native.js
+++ b/src/isomorphic/devtools/__tests__/ReactComponentTreeDevtool-test.native.js
@@ -119,13 +119,20 @@ describe('ReactComponentTreeDevtool', () => {
     // Ensure the tree is correct on every step.
     pairs.forEach(([element, expectedTree]) => {
       currentElement = element;
+
+      // Mount a new tree or update the existing tree.
       ReactNative.render(<Wrapper />, 1);
       expect(getActualTree()).toEqual(expectedTree);
+
+      // Purging should have no effect
+      // on the tree we expect to see.
       ReactComponentTreeDevtool.purgeUnmountedComponents();
       expect(getActualTree()).toEqual(expectedTree);
     });
+
+    // Unmounting the root node should purge
+    // the whole subtree automatically.
     ReactNative.unmountComponentAtNode(1);
-    ReactComponentTreeDevtool.purgeUnmountedComponents();
     expect(getActualTree()).toBe(undefined);
     expect(getRootDisplayNames()).toEqual([]);
     expect(getRegisteredDisplayNames()).toEqual([]);
@@ -134,10 +141,13 @@ describe('ReactComponentTreeDevtool', () => {
     // Ensure the tree is correct on every step.
     pairs.forEach(([element, expectedTree]) => {
       currentElement = element;
+
+      // Mount a new tree.
       ReactNative.render(<Wrapper />, 1);
-      ReactNative.unmountComponentAtNode(1);
       expect(getActualTree()).toEqual(expectedTree);
-      ReactComponentTreeDevtool.purgeUnmountedComponents();
+
+      // Unmounting should clean it up.
+      ReactNative.unmountComponentAtNode(1);
       expect(getActualTree()).toBe(undefined);
       expect(getRootDisplayNames()).toEqual([]);
       expect(getRegisteredDisplayNames()).toEqual([]);
@@ -1620,7 +1630,7 @@ describe('ReactComponentTreeDevtool', () => {
     assertTreeMatches([element, tree], {includeOwnerDisplayName: true});
   });
 
-  it('preserves unmounted components until purge', () => {
+  it('purges unmounted components automatically', () => {
     var renderBar = true;
     var fooInstance;
     var barInstance;
@@ -1654,31 +1664,15 @@ describe('ReactComponentTreeDevtool', () => {
     renderBar = false;
     ReactNative.render(<Foo />, 1);
     expect(
-      getTree(barInstance._debugID, {
-        includeParentDisplayName: true,
-        expectedParentID: fooInstance._debugID,
-      })
+      getTree(barInstance._debugID, {expectedParentID: null})
     ).toEqual({
-      displayName: 'Bar',
-      parentDisplayName: 'Foo',
+      displayName: 'Unknown',
       children: [],
     });
 
     ReactNative.unmountComponentAtNode(1);
     expect(
-      getTree(barInstance._debugID, {
-        includeParentDisplayName: true,
-        expectedParentID: fooInstance._debugID,
-      })
-    ).toEqual({
-      displayName: 'Bar',
-      parentDisplayName: 'Foo',
-      children: [],
-    });
-
-    ReactComponentTreeDevtool.purgeUnmountedComponents();
-    expect(
-      getTree(barInstance._debugID, {includeParentDisplayName: true})
+      getTree(barInstance._debugID, {expectedParentID: null})
     ).toEqual({
       displayName: 'Unknown',
       children: [],
@@ -1705,7 +1699,7 @@ describe('ReactComponentTreeDevtool', () => {
 
     ReactNative.unmountComponentAtNode(1);
     expect(ReactComponentTreeDevtool.getUpdateCount(viewID)).toEqual(0);
-    expect(ReactComponentTreeDevtool.getUpdateCount(imageID)).toEqual(2);
+    expect(ReactComponentTreeDevtool.getUpdateCount(imageID)).toEqual(0);
   });
 
   it('does not report top-level wrapper as a root', () => {
@@ -1717,12 +1711,6 @@ describe('ReactComponentTreeDevtool', () => {
 
     ReactNative.unmountComponentAtNode(1);
     expect(getRootDisplayNames()).toEqual([]);
-
-    ReactComponentTreeDevtool.purgeUnmountedComponents();
-    expect(getRootDisplayNames()).toEqual([]);
-
-    // This currently contains TopLevelWrapper until purge
-    // so we only check it at the very end.
     expect(getRegisteredDisplayNames()).toEqual([]);
   });
 });
diff --git a/src/isomorphic/devtools/__tests__/ReactNativeOperationHistoryDevtool-test.js b/src/isomorphic/devtools/__tests__/ReactNativeOperationHistoryDevtool-test.js
index 73ee7511d1ecb..769fe675b1edc 100644
--- a/src/isomorphic/devtools/__tests__/ReactNativeOperationHistoryDevtool-test.js
+++ b/src/isomorphic/devtools/__tests__/ReactNativeOperationHistoryDevtool-test.js
@@ -36,9 +36,10 @@ describe('ReactNativeOperationHistoryDevtool', () => {
   describe('mount', () => {
     it('gets recorded for native roots', () => {
       var node = document.createElement('div');
+      ReactNativeOperationHistoryDevtool._preventClearing = true;
       ReactDOM.render(<div><p>Hi.</p></div>, node);
-      var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
+      var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
       assertHistoryMatches([{
         instanceID: inst._debugID,
         type: 'mount',
@@ -53,7 +54,10 @@ describe('ReactNativeOperationHistoryDevtool', () => {
         return <div><p>Hi.</p></div>;
       }
       var node = document.createElement('div');
+
+      ReactNativeOperationHistoryDevtool._preventClearing = true;
       ReactDOM.render(<Foo />, node);
+
       var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
       assertHistoryMatches([{
         instanceID: inst._debugID,
@@ -70,6 +74,8 @@ describe('ReactNativeOperationHistoryDevtool', () => {
         return null;
       }
       var node = document.createElement('div');
+
+      ReactNativeOperationHistoryDevtool._preventClearing = true;
       ReactDOM.render(<Foo />, node);
 
       // Empty DOM components should be invisible to devtools.
@@ -82,11 +88,12 @@ describe('ReactNativeOperationHistoryDevtool', () => {
         return element;
       }
 
+      ReactNativeOperationHistoryDevtool._preventClearing = true;
+
       var node = document.createElement('div');
       element = null;
       ReactDOM.render(<Foo />, node);
 
-      ReactNativeOperationHistoryDevtool.clearHistory();
       element = <span />;
       ReactDOM.render(<Foo />, node);
       var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
@@ -104,12 +111,14 @@ describe('ReactNativeOperationHistoryDevtool', () => {
   describe('update styles', () => {
     it('gets recorded during mount', () => {
       var node = document.createElement('div');
+
+      ReactNativeOperationHistoryDevtool._preventClearing = true;
       ReactDOM.render(<div style={{
         color: 'red',
         backgroundColor: 'yellow',
       }} />, node);
-      var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
+      var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
       if (ReactDOMFeatureFlags.useCreateElement) {
         assertHistoryMatches([{
           instanceID: inst._debugID,
@@ -138,7 +147,7 @@ describe('ReactNativeOperationHistoryDevtool', () => {
       ReactDOM.render(<div />, node);
       var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
-      ReactNativeOperationHistoryDevtool.clearHistory();
+      ReactNativeOperationHistoryDevtool._preventClearing = true;
       ReactDOM.render(<div style={{ color: 'red' }} />, node);
       ReactDOM.render(<div style={{
         color: 'blue',
@@ -171,7 +180,7 @@ describe('ReactNativeOperationHistoryDevtool', () => {
       ReactDOM.render(<div />, node);
       var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
-      ReactNativeOperationHistoryDevtool.clearHistory();
+      ReactNativeOperationHistoryDevtool._preventClearing = true;
       ReactDOM.render(<div style={{
         color: 'red',
         backgroundColor: 'yellow',
@@ -196,9 +205,11 @@ describe('ReactNativeOperationHistoryDevtool', () => {
     describe('simple attribute', () => {
       it('gets recorded during mount', () => {
         var node = document.createElement('div');
+
+        ReactNativeOperationHistoryDevtool._preventClearing = true;
         ReactDOM.render(<div className="rad" tabIndex={42} />, node);
-        var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
+        var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
         if (ReactDOMFeatureFlags.useCreateElement) {
           assertHistoryMatches([{
             instanceID: inst._debugID,
@@ -228,10 +239,11 @@ describe('ReactNativeOperationHistoryDevtool', () => {
         ReactDOM.render(<div />, node);
         var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
-        ReactNativeOperationHistoryDevtool.clearHistory();
+        ReactNativeOperationHistoryDevtool._preventClearing = true;
         ReactDOM.render(<div className="rad" />, node);
         ReactDOM.render(<div className="mad" tabIndex={42} />, node);
         ReactDOM.render(<div tabIndex={43} />, node);
+
         assertHistoryMatches([{
           instanceID: inst._debugID,
           type: 'update attribute',
@@ -262,9 +274,10 @@ describe('ReactNativeOperationHistoryDevtool', () => {
         ReactDOM.render(<div />, node);
         var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
-        ReactNativeOperationHistoryDevtool.clearHistory();
+        ReactNativeOperationHistoryDevtool._preventClearing = true;
         ReactDOM.render(<div disabled={true} />, node);
         ReactDOM.render(<div disabled={false} />, node);
+
         assertHistoryMatches([{
           instanceID: inst._debugID,
           type: 'update attribute',
@@ -280,9 +293,11 @@ describe('ReactNativeOperationHistoryDevtool', () => {
     describe('custom attribute', () => {
       it('gets recorded during mount', () => {
         var node = document.createElement('div');
+
+        ReactNativeOperationHistoryDevtool._preventClearing = true;
         ReactDOM.render(<div data-x="rad" data-y={42} />, node);
-        var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
+        var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
         if (ReactDOMFeatureFlags.useCreateElement) {
           assertHistoryMatches([{
             instanceID: inst._debugID,
@@ -312,10 +327,11 @@ describe('ReactNativeOperationHistoryDevtool', () => {
         ReactDOM.render(<div />, node);
         var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
-        ReactNativeOperationHistoryDevtool.clearHistory();
+        ReactNativeOperationHistoryDevtool._preventClearing = true;
         ReactDOM.render(<div data-x="rad" />, node);
         ReactDOM.render(<div data-x="mad" data-y={42} />, node);
         ReactDOM.render(<div data-y={43} />, node);
+
         assertHistoryMatches([{
           instanceID: inst._debugID,
           type: 'update attribute',
@@ -343,9 +359,11 @@ describe('ReactNativeOperationHistoryDevtool', () => {
     describe('attribute on a web component', () => {
       it('gets recorded during mount', () => {
         var node = document.createElement('div');
+
+        ReactNativeOperationHistoryDevtool._preventClearing = true;
         ReactDOM.render(<my-component className="rad" tabIndex={42} />, node);
-        var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
+        var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
         if (ReactDOMFeatureFlags.useCreateElement) {
           assertHistoryMatches([{
             instanceID: inst._debugID,
@@ -375,10 +393,11 @@ describe('ReactNativeOperationHistoryDevtool', () => {
         ReactDOM.render(<my-component />, node);
         var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
-        ReactNativeOperationHistoryDevtool.clearHistory();
+        ReactNativeOperationHistoryDevtool._preventClearing = true;
         ReactDOM.render(<my-component className="rad" />, node);
         ReactDOM.render(<my-component className="mad" tabIndex={42} />, node);
         ReactDOM.render(<my-component tabIndex={43} />, node);
+
         assertHistoryMatches([{
           instanceID: inst._debugID,
           type: 'update attribute',
@@ -411,8 +430,9 @@ describe('ReactNativeOperationHistoryDevtool', () => {
         ReactDOM.render(<div>Hi.</div>, node);
         var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
-        ReactNativeOperationHistoryDevtool.clearHistory();
+        ReactNativeOperationHistoryDevtool._preventClearing = true;
         ReactDOM.render(<div>Bye.</div>, node);
+
         assertHistoryMatches([{
           instanceID: inst._debugID,
           type: 'replace text',
@@ -425,8 +445,9 @@ describe('ReactNativeOperationHistoryDevtool', () => {
         ReactDOM.render(<div dangerouslySetInnerHTML={{__html: 'Hi.'}} />, node);
         var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
-        ReactNativeOperationHistoryDevtool.clearHistory();
+        ReactNativeOperationHistoryDevtool._preventClearing = true;
         ReactDOM.render(<div>Bye.</div>, node);
+
         assertHistoryMatches([{
           instanceID: inst._debugID,
           type: 'replace text',
@@ -439,8 +460,9 @@ describe('ReactNativeOperationHistoryDevtool', () => {
         ReactDOM.render(<div><span /><p /></div>, node);
         var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
-        ReactNativeOperationHistoryDevtool.clearHistory();
+        ReactNativeOperationHistoryDevtool._preventClearing = true;
         ReactDOM.render(<div>Bye.</div>, node);
+
         assertHistoryMatches([{
           instanceID: inst._debugID,
           type: 'remove child',
@@ -460,8 +482,9 @@ describe('ReactNativeOperationHistoryDevtool', () => {
         var node = document.createElement('div');
         ReactDOM.render(<div>Hi.</div>, node);
 
-        ReactNativeOperationHistoryDevtool.clearHistory();
+        ReactNativeOperationHistoryDevtool._preventClearing = true;
         ReactDOM.render(<div>Hi.</div>, node);
+
         assertHistoryMatches([]);
       });
     });
@@ -473,8 +496,9 @@ describe('ReactNativeOperationHistoryDevtool', () => {
         var inst1 = ReactDOMComponentTree.getInstanceFromNode(node.firstChild.childNodes[0]);
         var inst2 = ReactDOMComponentTree.getInstanceFromNode(node.firstChild.childNodes[3]);
 
-        ReactNativeOperationHistoryDevtool.clearHistory();
+        ReactNativeOperationHistoryDevtool._preventClearing = true;
         ReactDOM.render(<div>{'Bye.'}{43}</div>, node);
+
         assertHistoryMatches([{
           instanceID: inst1._debugID,
           type: 'replace text',
@@ -490,8 +514,9 @@ describe('ReactNativeOperationHistoryDevtool', () => {
         var node = document.createElement('div');
         ReactDOM.render(<div>{'Hi.'}{42}</div>, node);
 
-        ReactNativeOperationHistoryDevtool.clearHistory();
+        ReactNativeOperationHistoryDevtool._preventClearing = true;
         ReactDOM.render(<div>{'Hi.'}{42}</div>, node);
+
         assertHistoryMatches([]);
       });
     });
@@ -509,9 +534,11 @@ describe('ReactNativeOperationHistoryDevtool', () => {
       ReactDOM.render(<Foo />, node);
       var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
-      ReactNativeOperationHistoryDevtool.clearHistory();
       element = <span />;
+
+      ReactNativeOperationHistoryDevtool._preventClearing = true;
       ReactDOM.render(<Foo />, node);
+
       assertHistoryMatches([{
         instanceID: inst._debugID,
         type: 'replace with',
@@ -528,11 +555,13 @@ describe('ReactNativeOperationHistoryDevtool', () => {
       var node = document.createElement('div');
       element = <span />;
       ReactDOM.render(<Foo />, node);
-      var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
-      ReactNativeOperationHistoryDevtool.clearHistory();
+      var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
       element = null;
+
+      ReactNativeOperationHistoryDevtool._preventClearing = true;
       ReactDOM.render(<Foo />, node);
+
       assertHistoryMatches([{
         instanceID: inst._debugID,
         type: 'replace with',
@@ -550,9 +579,11 @@ describe('ReactNativeOperationHistoryDevtool', () => {
       element = <div />;
       ReactDOM.render(<Foo />, node);
 
-      ReactNativeOperationHistoryDevtool.clearHistory();
       element = <div />;
+
+      ReactNativeOperationHistoryDevtool._preventClearing = true;
       ReactDOM.render(<Foo />, node);
+
       assertHistoryMatches([]);
     });
   });
@@ -563,11 +594,12 @@ describe('ReactNativeOperationHistoryDevtool', () => {
       ReactDOM.render(<div>Hi.</div>, node);
       var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
-      ReactNativeOperationHistoryDevtool.clearHistory();
+      ReactNativeOperationHistoryDevtool._preventClearing = true;
       ReactDOM.render(
         <div dangerouslySetInnerHTML={{__html: 'Bye.'}} />,
         node
       );
+
       assertHistoryMatches([{
         instanceID: inst._debugID,
         type: 'replace children',
@@ -583,11 +615,12 @@ describe('ReactNativeOperationHistoryDevtool', () => {
       );
       var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
-      ReactNativeOperationHistoryDevtool.clearHistory();
+      ReactNativeOperationHistoryDevtool._preventClearing = true;
       ReactDOM.render(
         <div dangerouslySetInnerHTML={{__html: 'Bye.'}} />,
         node
       );
+
       assertHistoryMatches([{
         instanceID: inst._debugID,
         type: 'replace children',
@@ -600,11 +633,12 @@ describe('ReactNativeOperationHistoryDevtool', () => {
       ReactDOM.render(<div><span /><p /></div>, node);
       var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
-      ReactNativeOperationHistoryDevtool.clearHistory();
+      ReactNativeOperationHistoryDevtool._preventClearing = true;
       ReactDOM.render(
         <div dangerouslySetInnerHTML={{__html: 'Hi.'}} />,
         node
       );
+
       assertHistoryMatches([{
         instanceID: inst._debugID,
         type: 'remove child',
@@ -627,11 +661,12 @@ describe('ReactNativeOperationHistoryDevtool', () => {
         node
       );
 
-      ReactNativeOperationHistoryDevtool.clearHistory();
+      ReactNativeOperationHistoryDevtool._preventClearing = true;
       ReactDOM.render(
         <div dangerouslySetInnerHTML={{__html: 'Hi.'}} />,
         node
       );
+
       assertHistoryMatches([]);
     });
   });
@@ -642,8 +677,9 @@ describe('ReactNativeOperationHistoryDevtool', () => {
       ReactDOM.render(<div><span /></div>, node);
       var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
-      ReactNativeOperationHistoryDevtool.clearHistory();
+      ReactNativeOperationHistoryDevtool._preventClearing = true;
       ReactDOM.render(<div><span /><p /></div>, node);
+
       assertHistoryMatches([{
         instanceID: inst._debugID,
         type: 'insert child',
@@ -658,8 +694,9 @@ describe('ReactNativeOperationHistoryDevtool', () => {
       ReactDOM.render(<div><span key="a" /><p key="b" /></div>, node);
       var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
-      ReactNativeOperationHistoryDevtool.clearHistory();
+      ReactNativeOperationHistoryDevtool._preventClearing = true;
       ReactDOM.render(<div><p key="b" /><span key="a" /></div>, node);
+
       assertHistoryMatches([{
         instanceID: inst._debugID,
         type: 'move child',
@@ -674,8 +711,9 @@ describe('ReactNativeOperationHistoryDevtool', () => {
       ReactDOM.render(<div><span key="a" /><p key="b" /></div>, node);
       var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
 
-      ReactNativeOperationHistoryDevtool.clearHistory();
+      ReactNativeOperationHistoryDevtool._preventClearing = true;
       ReactDOM.render(<div><span key="a" /></div>, node);
+
       assertHistoryMatches([{
         instanceID: inst._debugID,
         type: 'remove child',
diff --git a/src/renderers/dom/server/ReactServerRendering.js b/src/renderers/dom/server/ReactServerRendering.js
index 73ce86c46045d..ee57e07438e98 100644
--- a/src/renderers/dom/server/ReactServerRendering.js
+++ b/src/renderers/dom/server/ReactServerRendering.js
@@ -37,6 +37,9 @@ function renderToStringImpl(element, makeStaticMarkup) {
     transaction = ReactServerRenderingTransaction.getPooled(makeStaticMarkup);
 
     return transaction.perform(function() {
+      if (__DEV__) {
+        ReactInstrumentation.debugTool.onBeginFlush();
+      }
       var componentInstance = instantiateReactComponent(element);
       var markup = ReactReconciler.mountComponent(
         componentInstance,
@@ -49,6 +52,7 @@ function renderToStringImpl(element, makeStaticMarkup) {
         ReactInstrumentation.debugTool.onUnmountComponent(
           componentInstance._debugID
         );
+        ReactInstrumentation.debugTool.onEndFlush();
       }
       if (!makeStaticMarkup) {
         markup = ReactMarkupChecksum.addChecksumToMarkup(markup);
diff --git a/src/renderers/native/ReactNativeMount.js b/src/renderers/native/ReactNativeMount.js
index 0e5c4838bbdd8..0694ec262c2b5 100644
--- a/src/renderers/native/ReactNativeMount.js
+++ b/src/renderers/native/ReactNativeMount.js
@@ -216,8 +216,14 @@ var ReactNativeMount = {
     if (!instance) {
       return false;
     }
+    if (__DEV__) {
+      ReactInstrumentation.debugTool.onBeginFlush();
+    }
     ReactNativeMount.unmountComponentFromNode(instance, containerTag);
     delete ReactNativeMount._instancesByContainerID[containerTag];
+    if (__DEV__) {
+      ReactInstrumentation.debugTool.onEndFlush();
+    }
     return true;
   },