SERVER-10267 Remove in-place state from mods now that mutable and udpate driver handle it

21 files changed, 123 insertions, 228 deletions

diff --git a/src/mongo/db/ops/modifier_add_to_set.cpp b/src/mongo/db/ops/modifier_add_to_set.cpp
index 16b88051974..a35e2b4268a 100644
--- a/src/mongo/db/ops/modifier_add_to_set.cpp
+++ b/src/mongo/db/ops/modifier_add_to_set.cpp
@@ -262,10 +262,9 @@ namespace mongo {
             eachIter = eachIter.rightSibling();
         }
 
-        // If we didn't find any elements to add, then this is a no-op, and therefore in place.
+        // If we didn't find any elements to add, then this is a no-op.
         if (_preparedState->elementsToAdd.empty()) {
             _preparedState->noOp = execInfo->noOp = true;
-            execInfo->inPlace = true;
         }
 
         return Status::OK();
diff --git a/src/mongo/db/ops/modifier_add_to_set_test.cpp b/src/mongo/db/ops/modifier_add_to_set_test.cpp
index dd3a2d30ea4..0257741bdb6 100644
--- a/src/mongo/db/ops/modifier_add_to_set_test.cpp
+++ b/src/mongo/db/ops/modifier_add_to_set_test.cpp
@@ -124,7 +124,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
     }
 
@@ -135,7 +134,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_TRUE(execInfo.noOp);
 
         Document logDoc;
@@ -167,10 +165,10 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : [ 1 ] }"), doc);
 
         Document logDoc;
@@ -186,10 +184,10 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : [ 1 ] }"), doc);
 
         Document logDoc;
@@ -205,10 +203,10 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : [ 1, 2, 3 ] }"), doc);
 
         Document logDoc;
@@ -224,10 +222,10 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : [ 1, 2, 3 ] }"), doc);
 
         Document logDoc;
@@ -243,10 +241,10 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : [ 'x', 1 ] }"), doc);
 
         Document logDoc;
@@ -262,10 +260,10 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : [ 'x', 1, 2, 3 ] }"), doc);
 
         Document logDoc;
@@ -281,7 +279,6 @@ namespace {
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
         ASSERT_TRUE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
 
         Document logDoc;
         LogBuilder logBuilder(logDoc.root());
@@ -296,7 +293,6 @@ namespace {
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
         ASSERT_TRUE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
 
         Document logDoc;
         LogBuilder logBuilder(logDoc.root());
@@ -311,7 +307,6 @@ namespace {
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
         ASSERT_TRUE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
 
         Document logDoc;
         LogBuilder logBuilder(logDoc.root());
@@ -327,9 +322,9 @@ namespace {
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_FALSE(execInfo.inPlace);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : [ 1, 1, 2, 1, 2, 2, 3] }"), doc);
 
         Document logDoc;
@@ -346,9 +341,9 @@ namespace {
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_FALSE(execInfo.inPlace);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : [ 1, 1, 2, 1, 2, 2, 4, 3] }"), doc);
 
         Document logDoc;
diff --git a/src/mongo/db/ops/modifier_bit.cpp b/src/mongo/db/ops/modifier_bit.cpp
index ca20f02feed..df8332ecb12 100644
--- a/src/mongo/db/ops/modifier_bit.cpp
+++ b/src/mongo/db/ops/modifier_bit.cpp
@@ -34,7 +34,6 @@ namespace mongo {
             , idxFound(0)
             , elemFound(doc.end())
             , boundDollar("")
-            , inPlace(false)
             , noOp(false) {
         }
 
@@ -53,9 +52,6 @@ namespace mongo {
         // Value to be applied.
         SafeNum newValue;
 
-        // True if this update can be applied in place.
-        bool inPlace;
-
         // True if this update is a no-op
         bool noOp;
     };
@@ -189,19 +185,12 @@ namespace mongo {
             return Status(ErrorCodes::BadValue,
                           "Failed to apply $bit to current value");
 
-        // If the values are identical (same type, same value), then this is a no-op, and
-        // therefore in-place as well.
+        // If the values are identical (same type, same value), then this is a no-op.
         if (_preparedState->newValue.isIdentical(currentValue)) {
             _preparedState->noOp = execInfo->noOp = true;
-            _preparedState->inPlace = execInfo->inPlace = true;
             return Status::OK();
         }
 
-        // TODO: Cases where the type changes but size is the same.
-        if (currentValue.type() == _preparedState->newValue.type()) {
-            _preparedState->inPlace = execInfo->inPlace = true;
-        }
-
         return Status::OK();
     }
 
@@ -215,8 +204,6 @@ namespace mongo {
             return _preparedState->elemFound.setValueSafeNum(_preparedState->newValue);
         }
 
-        dassert(_preparedState->inPlace == false);
-
         //
         // Complete document path logic
         //
diff --git a/src/mongo/db/ops/modifier_bit_test.cpp b/src/mongo/db/ops/modifier_bit_test.cpp
index cd11f0246c1..79b940c2a77 100644
--- a/src/mongo/db/ops/modifier_bit_test.cpp
+++ b/src/mongo/db/ops/modifier_bit_test.cpp
@@ -123,7 +123,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
 
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
     }
 
@@ -134,7 +133,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
 
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_TRUE(execInfo.noOp);
 
         Document logDoc;
@@ -174,10 +172,10 @@ namespace {
 
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : 0 }"), doc);
 
         Document logDoc;
@@ -192,10 +190,10 @@ namespace {
 
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : 1 }"), doc);
 
         Document logDoc;
@@ -210,10 +208,10 @@ namespace {
 
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_TRUE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : 4 }"), doc);
 
         Document logDoc;
@@ -228,10 +226,10 @@ namespace {
 
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_TRUE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : 7 }"), doc);
 
         Document logDoc;
@@ -247,7 +245,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_TRUE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
 
         Document logDoc;
         LogBuilder logBuilder(logDoc.root());
@@ -262,7 +259,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_TRUE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
 
         Document logDoc;
         LogBuilder logBuilder(logDoc.root());
@@ -277,7 +273,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_TRUE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
 
         Document logDoc;
         LogBuilder logBuilder(logDoc.root());
@@ -292,7 +287,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_TRUE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
 
         Document logDoc;
         LogBuilder logBuilder(logDoc.root());
@@ -307,7 +301,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_FALSE(execInfo.inPlace);
     }
 
     TEST(InPlace, IntToLongOrIsNotInPlace) {
@@ -317,7 +310,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_FALSE(execInfo.inPlace);
     }
 
     TEST(NoOp, IntAnd) {
@@ -327,7 +319,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_TRUE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
 
         Document logDoc;
         LogBuilder logBuilder(logDoc.root());
@@ -342,7 +333,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_TRUE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
 
         Document logDoc;
         LogBuilder logBuilder(logDoc.root());
@@ -357,7 +347,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_TRUE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
 
         Document logDoc;
         LogBuilder logBuilder(logDoc.root());
@@ -373,7 +362,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_TRUE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
 
         Document logDoc;
         LogBuilder logBuilder(logDoc.root());
@@ -389,9 +377,9 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_FALSE(execInfo.inPlace);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : 1 }"), doc);
         ASSERT_EQUALS(mongo::NumberLong, doc.root()["a"].getType());
     }
@@ -403,9 +391,9 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_FALSE(execInfo.inPlace);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : 1 }"), doc);
         ASSERT_EQUALS(mongo::NumberLong, doc.root()["a"].getType());
     }
@@ -417,9 +405,9 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
 
         ASSERT_OK(mod.apply());
+        ASSERT_TRUE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : 0 }"), doc);
         ASSERT_EQUALS(mongo::NumberLong, doc.root()["a"].getType());
     }
@@ -431,9 +419,9 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
 
         ASSERT_OK(mod.apply());
+        ASSERT_TRUE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : 3 }"), doc);
         ASSERT_EQUALS(mongo::NumberLong, doc.root()["a"].getType());
     }
@@ -448,9 +436,9 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
 
         ASSERT_OK(mod.apply());
+        ASSERT_TRUE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(BSON("a" << static_cast<int>(1)), doc);
         ASSERT_EQUALS(mongo::NumberInt, doc.root()["a"].getType());
 
@@ -467,9 +455,9 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_FALSE(execInfo.inPlace);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(BSON("a" << static_cast<int>(0) << "b" << static_cast<int>(1)), doc);
         ASSERT_EQUALS(mongo::NumberInt, doc.root()["a"].getType());
 
diff --git a/src/mongo/db/ops/modifier_inc.cpp b/src/mongo/db/ops/modifier_inc.cpp
index eef9b0d2f64..e78ad09343c 100644
--- a/src/mongo/db/ops/modifier_inc.cpp
+++ b/src/mongo/db/ops/modifier_inc.cpp
@@ -35,7 +35,6 @@ namespace mongo {
             , elemFound(doc.end())
             , boundDollar("")
             , newValue()
-            , inPlace(false)
             , noOp(false) {
         }
 
@@ -54,9 +53,6 @@ namespace mongo {
         // Value to be applied
         SafeNum newValue;
 
-        // This $inc is in-place?
-        bool inPlace;
-
         // This $inc is a no-op?
         bool noOp;
     };
@@ -177,22 +173,12 @@ namespace mongo {
             return Status(ErrorCodes::BadValue,
                           "Failed to increment current value");
 
-        // If the values are identical (same type, same value), then this is a no-op, and
-        // therefore in-place as well.
+        // If the values are identical (same type, same value), then this is a no-op.
         if (_preparedState->newValue.isIdentical(currentValue)) {
             _preparedState->noOp = execInfo->noOp = true;
-            _preparedState->inPlace = execInfo->inPlace = true;
             return Status::OK();
         }
 
-        // If the types are the same, this can be done in place.
-        //
-        // TODO: Potentially, cases where $inc results in a mixed type of the same size could
-        // be in-place as well, but we don't currently handle them.
-        if (_preparedState->newValue.type() == currentValue.type()) {
-            _preparedState->inPlace = execInfo->inPlace = true;
-        }
-
         return Status::OK();
     }
 
@@ -206,8 +192,6 @@ namespace mongo {
             return _preparedState->elemFound.setValueSafeNum(_preparedState->newValue);
         }
 
-        dassert(_preparedState->inPlace == false);
-
         //
         // Complete document path logic
         //
diff --git a/src/mongo/db/ops/modifier_inc_test.cpp b/src/mongo/db/ops/modifier_inc_test.cpp
index b5e76e8cfde..f399c31ffb2 100644
--- a/src/mongo/db/ops/modifier_inc_test.cpp
+++ b/src/mongo/db/ops/modifier_inc_test.cpp
@@ -113,7 +113,7 @@ namespace {
         ASSERT_OK(incMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_TRUE(execInfo.inPlace);
+        ASSERT_TRUE(doc.isInPlaceModeEnabled());
         ASSERT_FALSE(execInfo.noOp);
     }
 
@@ -148,10 +148,10 @@ namespace {
 
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(incMod.prepare(doc.root(), "", &execInfo));
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(incMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : 1 }"), doc);
 
         Document logDoc;
@@ -166,7 +166,6 @@ namespace {
 
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(incMod.prepare(doc.root(), "", &execInfo));
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         Document logDoc;
@@ -181,10 +180,10 @@ namespace {
 
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(incMod.prepare(doc.root(), "", &execInfo));
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(incMod.apply());
+        ASSERT_TRUE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : 3 }"), doc);
 
         Document logDoc;
@@ -199,10 +198,10 @@ namespace {
 
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(incMod.prepare(doc.root(), "", &execInfo));
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(incMod.apply());
+        ASSERT_TRUE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : { b : 3 } }"), doc);
 
         Document logDoc;
@@ -217,7 +216,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(incMod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
     }
 
     TEST(InPlace, LongToLong) {
@@ -226,7 +224,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(incMod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
     }
 
     TEST(InPlace, DoubleToDouble) {
@@ -235,7 +232,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(incMod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
     }
 
     TEST(NoOp, Int) {
@@ -244,7 +240,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(incMod.prepare(doc.root(), "", &execInfo));
         ASSERT_TRUE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
     }
 
     TEST(NoOp, Long) {
@@ -253,7 +248,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(incMod.prepare(doc.root(), "", &execInfo));
         ASSERT_TRUE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
     }
 
     TEST(NoOp, Double) {
@@ -262,7 +256,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(incMod.prepare(doc.root(), "", &execInfo));
         ASSERT_TRUE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
     }
 
     TEST(Upcasting, UpcastIntToLong) {
@@ -276,9 +269,9 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(incMod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_FALSE(execInfo.inPlace);
 
         ASSERT_OK(incMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : 1 }"), doc);
         ASSERT_EQUALS(mongo::NumberLong, doc.root()["a"].getType());
 
@@ -300,9 +293,9 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(incMod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_FALSE(execInfo.inPlace);
 
         ASSERT_OK(incMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : 1.0 }"), doc);
         ASSERT_EQUALS(mongo::NumberDouble, doc.root()["a"].getType());
 
@@ -324,9 +317,9 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(incMod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_FALSE(execInfo.inPlace);
 
         ASSERT_OK(incMod.apply());
+        ASSERT_TRUE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : 1.0 }"), doc);
         ASSERT_EQUALS(mongo::NumberDouble, doc.root()["a"].getType());
 
@@ -347,9 +340,9 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(incMod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
 
         ASSERT_OK(incMod.apply());
+        ASSERT_TRUE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : 2.0 }"), doc);
         ASSERT_EQUALS(mongo::NumberDouble, doc.root()["a"].getType());
 
@@ -373,11 +366,11 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(incMod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_FALSE(execInfo.inPlace);
 
         const long long target_value = static_cast<long long>(initial_value) + 1;
 
         ASSERT_OK(incMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(BSON("a" << target_value), doc);
     }
 
@@ -391,11 +384,11 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(incMod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_FALSE(execInfo.inPlace);
 
         const long long target_value = static_cast<long long>(initial_value) - 1;
 
         ASSERT_OK(incMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(BSON("a" << target_value), doc);
     }
 
@@ -407,17 +400,17 @@ namespace {
 
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(incMod.prepare(doc1.root(), "", &execInfo));
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(incMod.apply());
+        ASSERT_TRUE(doc1.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : 2 }"), doc1);
 
         ASSERT_OK(incMod.prepare(doc2.root(), "", &execInfo));
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(incMod.apply());
+        ASSERT_TRUE(doc2.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : 2 }"), doc2);
     }
 
diff --git a/src/mongo/db/ops/modifier_interface.h b/src/mongo/db/ops/modifier_interface.h
index 3341de8ba20..9d39bb67947 100644
--- a/src/mongo/db/ops/modifier_interface.h
+++ b/src/mongo/db/ops/modifier_interface.h
@@ -141,7 +141,7 @@ namespace mongo {
             ANY_CONTEXT
         };
 
-        ExecInfo() : inPlace(false), noOp(false), context(ANY_CONTEXT) {
+        ExecInfo() : noOp(false), context(ANY_CONTEXT) {
             for (int i = 0; i < MAX_NUM_FIELDS; i++) {
                 fieldRef[i] = NULL;
             }
@@ -149,7 +149,6 @@ namespace mongo {
 
         // The fields of concern to the driver: no other op may modify the fields listed here.
         FieldRef* fieldRef[MAX_NUM_FIELDS]; // not owned here
-        bool inPlace;
         bool noOp;
         UpdateContext context;
     };
diff --git a/src/mongo/db/ops/modifier_object_replace.h b/src/mongo/db/ops/modifier_object_replace.h
index f81ec8de299..df175b4fd90 100644
--- a/src/mongo/db/ops/modifier_object_replace.h
+++ b/src/mongo/db/ops/modifier_object_replace.h
@@ -50,7 +50,7 @@ namespace mongo {
 
         /**
          * Registers the that 'root' is in the document that we want to fully replace.
-         * prepare() returns OK and always fills 'execInfo' with false for inPlace and true for
+         * prepare() returns OK and always fills 'execInfo' with true for
          * noOp.
          */
         virtual Status prepare(mutablebson::Element root,
diff --git a/src/mongo/db/ops/modifier_pop.cpp b/src/mongo/db/ops/modifier_pop.cpp
index b70b69d3d07..fcb7e6f2c9e 100644
--- a/src/mongo/db/ops/modifier_pop.cpp
+++ b/src/mongo/db/ops/modifier_pop.cpp
@@ -128,7 +128,7 @@ namespace mongo {
 
             // No children, nothing to do -- not an error state
             if (!_preparedState->pathFoundElement.hasChildren()) {
-                execInfo->noOp = execInfo->inPlace = true;
+                execInfo->noOp = true;
             } else {
                 _preparedState->elementToRemove = _fromTop ?
                                 _preparedState->pathFoundElement.leftChild() :
@@ -136,7 +136,7 @@ namespace mongo {
             }
         } else {
             // Let the caller know we can't do anything given the mod, _fieldRef, and doc.
-            execInfo->noOp = execInfo->inPlace = true;
+            execInfo->noOp = true;
             _preparedState->pathFoundElement = root.getDocument().end();
 
             //okay if path not found
diff --git a/src/mongo/db/ops/modifier_pop_test.cpp b/src/mongo/db/ops/modifier_pop_test.cpp
index 5e278e9ac31..f1fedd08993 100644
--- a/src/mongo/db/ops/modifier_pop_test.cpp
+++ b/src/mongo/db/ops/modifier_pop_test.cpp
@@ -104,7 +104,6 @@ namespace {
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "s");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_TRUE(execInfo.noOp);
 
         Document logDoc;
@@ -121,7 +120,6 @@ namespace {
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
     }
 
@@ -133,10 +131,10 @@ namespace {
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson(("{a: [1]}")), doc);
     }
 
@@ -148,7 +146,6 @@ namespace {
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
     }
 
@@ -160,10 +157,10 @@ namespace {
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson(("{a: [2]}")), doc);
     }
 
@@ -175,10 +172,10 @@ namespace {
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson(("{a: [1]}")), doc);
     }
 
@@ -190,10 +187,10 @@ namespace {
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson(("{a:[1]}")), doc);
 
         Document logDoc;
@@ -210,7 +207,6 @@ namespace {
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_TRUE(execInfo.noOp);
     }
 
@@ -222,10 +218,10 @@ namespace {
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson(("{a:[]}")), doc);
 
         Document logDoc;
@@ -242,10 +238,10 @@ namespace {
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.0");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson(("{a:[[1], 1]}")), doc);
 
         Document logDoc;
@@ -262,10 +258,10 @@ namespace {
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.0");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson(("{a:[[], 1]}")), doc);
 
         Document logDoc;
@@ -281,6 +277,5 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_TRUE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
     }
 } // unnamed namespace
diff --git a/src/mongo/db/ops/modifier_pull.cpp b/src/mongo/db/ops/modifier_pull.cpp
index 0e886328284..ddd95200392 100644
--- a/src/mongo/db/ops/modifier_pull.cpp
+++ b/src/mongo/db/ops/modifier_pull.cpp
@@ -135,7 +135,6 @@ namespace mongo {
             _preparedState->idxFound < (_fieldRef.numParts() - 1)) {
             // If no target element exists, then there is nothing to do here.
             _preparedState->noOp = execInfo->noOp = true;
-            execInfo->inPlace = true;
             return Status::OK();
         }
 
@@ -148,7 +147,6 @@ namespace mongo {
         // If the array is empty, there is nothing to pull, so this is a noop.
         if (!_preparedState->elemFound.hasChildren()) {
             _preparedState->noOp = execInfo->noOp = true;
-            execInfo->inPlace = true;
             return Status::OK();
         }
 
@@ -165,7 +163,6 @@ namespace mongo {
         // If we didn't find any elements to add, then this is a no-op, and therefore in place.
         if (_preparedState->elementsToRemove.empty()) {
             _preparedState->noOp = execInfo->noOp = true;
-            execInfo->inPlace = true;
         }
 
         return Status::OK();
diff --git a/src/mongo/db/ops/modifier_pull_all.cpp b/src/mongo/db/ops/modifier_pull_all.cpp
index f805dd8560d..e4ca877e419 100644
--- a/src/mongo/db/ops/modifier_pull_all.cpp
+++ b/src/mongo/db/ops/modifier_pull_all.cpp
@@ -144,7 +144,7 @@ namespace mongo {
 
             // No children, nothing to do -- not an error state
             if (!_preparedState->pathFoundElement.hasChildren()) {
-                execInfo->inPlace = execInfo->noOp = true;
+                execInfo->noOp = true;
             } else {
                 mutablebson::Element elem = _preparedState->pathFoundElement.leftChild();
                 while (elem.ok()) {
@@ -159,13 +159,12 @@ namespace mongo {
 
                 // Nothing to remove so it is a noOp.
                 if (_preparedState->elementsToRemove.empty())
-                    execInfo->inPlace = execInfo->noOp = true;
+                    execInfo->noOp = true;
             }
 
         } else {
             // Let the caller know we can't do anything given the mod, _fieldRef, and doc.
             execInfo->noOp = true;
-            execInfo->inPlace = true;
 
 
             //okay if path not found
diff --git a/src/mongo/db/ops/modifier_pull_all_test.cpp b/src/mongo/db/ops/modifier_pull_all_test.cpp
index 1053cf8d74d..85899c9ace1 100644
--- a/src/mongo/db/ops/modifier_pull_all_test.cpp
+++ b/src/mongo/db/ops/modifier_pull_all_test.cpp
@@ -99,9 +99,9 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_FALSE(execInfo.inPlace);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : ['a', {r:1, b:2}] }"), doc);
     }
 
@@ -112,9 +112,9 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_TRUE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
 
         ASSERT_OK(mod.apply());
+        ASSERT_TRUE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : [1, 'a', {r:1, b:2}] }"), doc);
     }
 
@@ -125,9 +125,9 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_FALSE(execInfo.inPlace);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : [{r:1, b:2}] }"), doc);
     }
 
@@ -138,9 +138,9 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_FALSE(execInfo.inPlace);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : [] }"), doc);
 
         Document logDoc;
@@ -156,9 +156,9 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_FALSE(execInfo.inPlace);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : [] }"), doc);
 
         Document logDoc;
@@ -174,9 +174,9 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_FALSE(execInfo.noOp);
-        ASSERT_FALSE(execInfo.inPlace);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : [] }"), doc);
 
         Document logDoc;
@@ -192,7 +192,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_TRUE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
 
         Document logDoc;
         LogBuilder logBuilder(logDoc.root());
@@ -207,7 +206,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_TRUE(execInfo.noOp);
-        ASSERT_TRUE(execInfo.inPlace);
 
         Document logDoc;
         LogBuilder logBuilder(logDoc.root());
diff --git a/src/mongo/db/ops/modifier_pull_test.cpp b/src/mongo/db/ops/modifier_pull_test.cpp
index 064d717006a..d8239dfc36b 100644
--- a/src/mongo/db/ops/modifier_pull_test.cpp
+++ b/src/mongo/db/ops/modifier_pull_test.cpp
@@ -79,7 +79,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_TRUE(execInfo.noOp);
 
         Document logDoc;
@@ -95,7 +94,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
     }
 
@@ -122,7 +120,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_TRUE(execInfo.noOp);
 
         Document logDoc;
@@ -138,7 +135,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b.c.d");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_TRUE(execInfo.noOp);
 
         Document logDoc;
@@ -154,7 +150,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_TRUE(execInfo.noOp);
 
         Document logDoc;
@@ -170,7 +165,6 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_TRUE(execInfo.noOp);
 
         Document logDoc;
@@ -186,10 +180,10 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : [ 1, 2, 3, 4, 5 ] }"), doc);
 
         Document logDoc;
@@ -205,10 +199,10 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : [ 1, 2, 3, 4, 5 ] }"), doc);
 
         Document logDoc;
@@ -224,10 +218,10 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{ a : [] }"), doc);
 
         Document logDoc;
@@ -265,10 +259,10 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson(strings[2]), doc);
 
         Document logDoc;
@@ -300,10 +294,10 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson(strings[2]), doc);
 
         Document logDoc;
@@ -335,10 +329,10 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson(strings[2]), doc);
 
         Document logDoc;
@@ -369,10 +363,10 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson(strings[2]), doc);
 
         Document logDoc;
@@ -403,10 +397,10 @@ namespace {
         ModifierInterface::ExecInfo execInfo;
         ASSERT_OK(mod.prepare(doc.root(), "", &execInfo));
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(mod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson(strings[2]), doc);
 
         Document logDoc;
diff --git a/src/mongo/db/ops/modifier_push_test.cpp b/src/mongo/db/ops/modifier_push_test.cpp
index df12ff2fc2c..aececbe3b3b 100644
--- a/src/mongo/db/ops/modifier_push_test.cpp
+++ b/src/mongo/db/ops/modifier_push_test.cpp
@@ -466,10 +466,10 @@ namespace {
         ASSERT_OK(pushMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(pushMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: [1]}"), doc);
 
         Document logDoc;
@@ -487,10 +487,10 @@ namespace {
         ASSERT_OK(pushMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(pushMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: [1]}"), doc);
 
         Document logDoc;
@@ -508,10 +508,10 @@ namespace {
         ASSERT_OK(pushMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(pushMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: [0,1]}"), doc);
 
         Document logDoc;
@@ -541,10 +541,10 @@ namespace {
         ASSERT_OK(pushMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(pushMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: [{b:1}]}"), doc);
 
         Document logDoc;
@@ -562,10 +562,10 @@ namespace {
         ASSERT_OK(pushMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(pushMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: [{b:1}]}"), doc);
 
         Document logDoc;
@@ -583,10 +583,10 @@ namespace {
         ASSERT_OK(pushMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(pushMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: [{b:0},{b:1}]}"), doc);
 
         Document logDoc;
@@ -609,10 +609,10 @@ namespace {
         ASSERT_OK(pushMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "choices.first.votes");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(pushMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson(   "{ _id : 1 , "
                                   "  question : 'a', "
                                   "  choices : { "
@@ -641,10 +641,10 @@ namespace {
         ASSERT_OK(pushMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(pushMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(doc, fromjson("{a: [1]}"));
 
         Document logDoc;
@@ -662,10 +662,10 @@ namespace {
         ASSERT_OK(pushMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(pushMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(doc, fromjson("{a: [1]}"));
 
         Document logDoc;
@@ -683,10 +683,10 @@ namespace {
         ASSERT_OK(pushMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(pushMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_TRUE(checkDoc(doc, fromjson("{a: [0,1,2]}")));
 
         Document logDoc;
@@ -716,10 +716,10 @@ namespace {
         ASSERT_OK(pushMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(pushMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: [1]}"), doc);
 
         Document logDoc;
@@ -737,10 +737,10 @@ namespace {
         ASSERT_OK(pushMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(pushMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: [1]}"), doc);
 
         Document logDoc;
@@ -758,10 +758,10 @@ namespace {
         ASSERT_OK(pushMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(pushMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: [1, 2]}"), doc);
 
         Document logDoc;
@@ -779,10 +779,10 @@ namespace {
         ASSERT_OK(pushMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(pushMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: [0,1]}"), doc);
 
         Document logDoc;
@@ -800,10 +800,10 @@ namespace {
         ASSERT_OK(pushMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(pushMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: [0,1,2]}"), doc);
 
         Document logDoc;
@@ -927,10 +927,10 @@ namespace {
             ASSERT_OK(mod().prepare(doc.root(), "", &execInfo));
 
             ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-            ASSERT_FALSE(execInfo.inPlace);
             ASSERT_FALSE(execInfo.noOp);
 
             ASSERT_OK(mod().apply());
+            ASSERT_FALSE(doc.isInPlaceModeEnabled());
 
             vector<int> combinedVec;
             combineVec(docArray,   /* a: []  */
@@ -958,10 +958,10 @@ namespace {
             ASSERT_OK(mod().prepare(doc.root(), "", &execInfo));
 
             ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-            ASSERT_FALSE(execInfo.inPlace);
             ASSERT_FALSE(execInfo.noOp);
 
             ASSERT_OK(mod().apply());
+            ASSERT_FALSE(doc.isInPlaceModeEnabled());
 
             vector<int> combinedVec;
             combineVec(docArray,  /* a: [2, 3] */
@@ -1000,10 +1000,10 @@ namespace {
                         ASSERT_OK(mod().prepare(doc.root(), "", &execInfo));
 
                         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-                        ASSERT_FALSE(execInfo.inPlace);
                         ASSERT_FALSE(execInfo.noOp);
 
                         ASSERT_OK(mod().apply());
+                        ASSERT_FALSE(doc.isInPlaceModeEnabled());
 
                         vector<BSONObj> combinedVec;
                         combineAndSortVec(docArray,  /* a: [] */
@@ -1054,10 +1054,10 @@ namespace {
                         ASSERT_OK(mod().prepare(doc.root(), "", &execInfo));
 
                         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-                        ASSERT_FALSE(execInfo.inPlace);
                         ASSERT_FALSE(execInfo.noOp);
 
                         ASSERT_OK(mod().apply());
+                        ASSERT_FALSE(doc.isInPlaceModeEnabled());
 
                         vector<BSONObj> combinedVec;
                         combineAndSortVec(docArray,  /* a: [{a:2,b:3},{a:3,:b1}] */
diff --git a/src/mongo/db/ops/modifier_rename.cpp b/src/mongo/db/ops/modifier_rename.cpp
index af28f5f06e1..680195ece71 100644
--- a/src/mongo/db/ops/modifier_rename.cpp
+++ b/src/mongo/db/ops/modifier_rename.cpp
@@ -130,7 +130,7 @@ namespace mongo {
 
         // If we can't find the full element in the from field then we can't do anything.
         if (!status.isOK()) {
-            execInfo->inPlace = execInfo->noOp = true;
+            execInfo->noOp = true;
             _preparedState->fromElemFound = root.getDocument().end();
 
             // TODO: remove this special case from existing behavior
@@ -183,7 +183,7 @@ namespace mongo {
         execInfo->fieldRef[0] = &_fromFieldRef;
         execInfo->fieldRef[1] = &_toFieldRef;
 
-        execInfo->inPlace = execInfo->noOp = false;
+        execInfo->noOp = false;
 
         return Status::OK();
     }
diff --git a/src/mongo/db/ops/modifier_rename_test.cpp b/src/mongo/db/ops/modifier_rename_test.cpp
index 6c6065c2303..a63d0d5fedb 100644
--- a/src/mongo/db/ops/modifier_rename_test.cpp
+++ b/src/mongo/db/ops/modifier_rename_test.cpp
@@ -130,10 +130,10 @@ namespace {
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
         ASSERT_EQUALS(execInfo.fieldRef[1]->dottedField(), "b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(doc, fromjson("{b:2}"));
 
         Document logDoc;
@@ -152,10 +152,10 @@ namespace {
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
         ASSERT_EQUALS(execInfo.fieldRef[1]->dottedField(), "b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(doc, fromjson("{b:2}"));
 
         Document logDoc;
@@ -174,10 +174,10 @@ namespace {
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.c");
         ASSERT_EQUALS(execInfo.fieldRef[1]->dottedField(), "b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(doc, fromjson("{a: {}, b:{ d: 6}}"));
 
         Document logDoc;
@@ -196,10 +196,10 @@ namespace {
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
         ASSERT_EQUALS(execInfo.fieldRef[1]->dottedField(), "c.r.d");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(doc, fromjson("{b:1, c: { r: { d: 2}}}"));
 
         Document logDoc;
@@ -218,10 +218,10 @@ namespace {
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
         ASSERT_EQUALS(execInfo.fieldRef[1]->dottedField(), "b.c.d");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(doc, fromjson("{b: {c: {d: 2}}}"));
 
         Document logDoc;
@@ -240,10 +240,10 @@ namespace {
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
         ASSERT_EQUALS(execInfo.fieldRef[1]->dottedField(), "b.c.d");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(doc, fromjson("{b: {c: {d: [ {a:2, b:1} ]}}}"));
 
         Document logDoc;
diff --git a/src/mongo/db/ops/modifier_set.cpp b/src/mongo/db/ops/modifier_set.cpp
index 1a566d7b1c9..842cffd87c2 100644
--- a/src/mongo/db/ops/modifier_set.cpp
+++ b/src/mongo/db/ops/modifier_set.cpp
@@ -32,7 +32,6 @@ namespace mongo {
             , idxFound(0)
             , elemFound(doc.end())
             , boundDollar("")
-            , inPlace(false)
             , noOp(false) {
         }
 
@@ -48,9 +47,6 @@ namespace mongo {
         // Value to bind to a $-positional field, if one is provided.
         std::string boundDollar;
 
-        // Could this mod be applied in place?
-        bool inPlace;
-
         // This $set is a no-op?
         bool noOp;
 
@@ -167,14 +163,6 @@ namespace mongo {
             return Status::OK();
         }
 
-        // We may allow this $set to be in place if the value being set and the existing one
-        // have the same size.
-        if (_val.isNumber() &&
-            (_preparedState->elemFound != root.getDocument().end()) &&
-            (_val.type() == _preparedState->elemFound.getType())) {
-            execInfo->inPlace = _preparedState->inPlace = true;
-        }
-
         // If the value being $set is the same as the one already in the doc, than this is a
         // noOp.
         if (_preparedState->elemFound.ok() &&
@@ -196,8 +184,6 @@ namespace mongo {
             return _preparedState->elemFound.setValueBSONElement(_val);
         }
 
-        dassert(!_preparedState->inPlace);
-
         //
         // Complete document path logic
         //
diff --git a/src/mongo/db/ops/modifier_set_test.cpp b/src/mongo/db/ops/modifier_set_test.cpp
index daa2f1ae852..05351d7db9e 100644
--- a/src/mongo/db/ops/modifier_set_test.cpp
+++ b/src/mongo/db/ops/modifier_set_test.cpp
@@ -105,7 +105,6 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_TRUE(execInfo.noOp);
     }
 
@@ -117,7 +116,6 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
         ASSERT_EQUALS(execInfo.context, ModifierInterface::ExecInfo::INSERT_CONTEXT);
     }
@@ -130,10 +128,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: 2}"), doc);
     }
 
@@ -145,10 +143,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_TRUE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: 2}"), doc);
     }
 
@@ -160,10 +158,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: 2}"), doc);
     }
 
@@ -175,10 +173,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: 2}"), doc);
     }
 
@@ -190,10 +188,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{b: 1, a: 2}"), doc);
     }
 
@@ -224,7 +222,6 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_TRUE(execInfo.noOp);
     }
 
@@ -252,10 +249,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_TRUE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: {b: 2}}"), doc);
     }
 
@@ -267,10 +264,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: {b: 2}}"), doc);
     }
 
@@ -282,10 +279,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: {b: 2}}"), doc);
     }
 
@@ -297,10 +294,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: {c: 1, b: 2}}"), doc);
     }
 
@@ -312,10 +309,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{c: 1, a: {b: 2}}"), doc);
     }
 
@@ -327,10 +324,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: {b: 2}}"), doc);
     }
 
@@ -342,10 +339,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{'a.b':4, a: {b: 2}}"), doc);
     }
 
@@ -361,7 +358,6 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_TRUE(execInfo.noOp);
     }
 
@@ -381,10 +377,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_TRUE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: [{b: 0},{b: 1},{b: 2}]}"), doc);
     }
 
@@ -396,10 +392,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: [{b: 0},{b: 1},{b: 2}]}"), doc);
     }
 
@@ -411,10 +407,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: [{b: 0},null,{b: 2}]}"), doc);
     }
 
@@ -426,10 +422,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: {b: 0, '2': {b: 2}}}"), doc);
     }
 
@@ -441,10 +437,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_TRUE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: {'2': {b: 2}}}"), doc);
     }
 
@@ -456,10 +452,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: {'2': {c: 1, b: 2}}}"), doc);
     }
 
@@ -471,10 +467,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: {'2': {b: 2}}}"), doc);
     }
 
@@ -486,10 +482,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: [null, null, {b: 2}]}"), doc);
     }
 
@@ -501,10 +497,10 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(setMod.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: {'2': {b: 2}}}"), doc);
     }
 
@@ -565,7 +561,6 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.1.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_TRUE(execInfo.noOp);
     }
 
@@ -577,7 +572,6 @@ namespace {
         ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.1.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
     }
 
diff --git a/src/mongo/db/ops/modifier_unset.cpp b/src/mongo/db/ops/modifier_unset.cpp
index 1a2fecec4d5..23feeaa60b6 100644
--- a/src/mongo/db/ops/modifier_unset.cpp
+++ b/src/mongo/db/ops/modifier_unset.cpp
@@ -31,7 +31,6 @@ namespace mongo {
             , idxFound(0)
             , elemFound(doc.end())
             , boundDollar("")
-            , inPlace(false)
             , noOp(false) {
         }
 
@@ -47,9 +46,6 @@ namespace mongo {
         // Value to bind to a $-positional field, if one is provided.
         std::string boundDollar;
 
-        // Could this mod be applied in place?
-        bool inPlace;
-
         // This $set is a no-op?
         bool noOp;
 
@@ -120,7 +116,6 @@ namespace mongo {
         if (!status.isOK() ||
             _preparedState->idxFound != (_fieldRef.numParts() -1)) {
             execInfo->noOp = _preparedState->noOp = true;
-            execInfo->inPlace = _preparedState->noOp = true;
             execInfo->fieldRef[0] = &_fieldRef;
 
             return Status::OK();
@@ -137,11 +132,9 @@ namespace mongo {
         // field boundaries must change.
         //
         // TODO:
-        // execInfo->inPlace = true;
         // mutablebson::Element curr = _preparedState->elemFound;
         // while (curr.ok()) {
         //     if (curr.rightSibling().ok()) {
-        //         execInfo->inPlace = false;
         //     }
         //     curr = curr.parent();
         // }
diff --git a/src/mongo/db/ops/modifier_unset_test.cpp b/src/mongo/db/ops/modifier_unset_test.cpp
index f2a1416a111..20e522c21ee 100644
--- a/src/mongo/db/ops/modifier_unset_test.cpp
+++ b/src/mongo/db/ops/modifier_unset_test.cpp
@@ -86,7 +86,6 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_TRUE(execInfo.noOp);
     }
 
@@ -98,10 +97,10 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(modUnset.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{b: 2}"), doc);
     }
 
@@ -113,10 +112,10 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace); // TODO turn in-place on for this.
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(modUnset.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled()); // TODO turn in-place on for this.
         ASSERT_EQUALS(fromjson("{x: 0}"), doc);
     }
 
@@ -128,10 +127,10 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace); // TODO turn in-place on for this.
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(modUnset.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled()); // TODO turn in-place on for this.
         ASSERT_EQUALS(fromjson("{}"), doc);
     }
 
@@ -143,10 +142,10 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(modUnset.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{c: 2}"), doc);
     }
 
@@ -159,7 +158,6 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
-        ASSERT_FALSE(execInfo.inPlace); // TODO turn in-place on for this.
         ASSERT_FALSE(execInfo.noOp);
 
         Document logDoc;
@@ -180,7 +178,6 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_TRUE(execInfo.noOp);
     }
 
@@ -192,10 +189,10 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(modUnset.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a:{}, c:2}"), doc);
     }
 
@@ -207,10 +204,10 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
-        ASSERT_FALSE(execInfo.inPlace); // TODO turn in-place on for this.
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(modUnset.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled()); // TODO turn in-place on for this.
         ASSERT_EQUALS(fromjson("{x: 0, a:{}}"), doc);
     }
 
@@ -222,10 +219,10 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
-        ASSERT_FALSE(execInfo.inPlace); // TODO turn in-place on for this.
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(modUnset.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled()); // TODO turn in-place on for this.
         ASSERT_EQUALS(fromjson("{a: {}}"), doc);
     }
 
@@ -241,7 +238,6 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.0");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_TRUE(execInfo.noOp);
     }
 
@@ -253,10 +249,10 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.0");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(modUnset.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a:[null,1,2]}"), doc);
     }
 
@@ -268,10 +264,10 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.0");
-        ASSERT_FALSE(execInfo.inPlace); // TODO turn in-place on for this.
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(modUnset.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled()); // TODO turn in-place on for this.
         ASSERT_EQUALS(fromjson("{b:1, a:[null]}"), doc);
     }
 
@@ -284,10 +280,10 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.0");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(modUnset.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a:[null], b:1}"), doc);
     }
 
@@ -299,10 +295,10 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.0.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(modUnset.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a:[{}]}"), doc);
     }
 
@@ -314,10 +310,10 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.0");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(modUnset.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a:[null]}"), doc);
     }
 
@@ -346,7 +342,6 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "1", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.1.b");
-        ASSERT_TRUE(execInfo.inPlace);
         ASSERT_TRUE(execInfo.noOp);
     }
 
@@ -366,10 +361,10 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "0", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.0.b");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(modUnset.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: [{}, {c:1}]}"), doc);
     }
 
@@ -381,10 +376,10 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "0", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.0");
-        ASSERT_FALSE(execInfo.inPlace);
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(modUnset.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled());
         ASSERT_EQUALS(fromjson("{a: [null, {c:1}]}"), doc);
     }
 
@@ -396,10 +391,10 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "0", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.0.b");
-        ASSERT_FALSE(execInfo.inPlace); // TODO turn in-place on for this.
         ASSERT_FALSE(execInfo.noOp);
 
         ASSERT_OK(modUnset.apply());
+        ASSERT_FALSE(doc.isInPlaceModeEnabled()); // TODO turn in-place on for this.
         ASSERT_EQUALS(fromjson("{b:1, a:[{}]}"), doc);
     }
 
@@ -411,7 +406,6 @@ namespace {
         ASSERT_OK(modUnset.prepare(doc.root(), "0", &execInfo));
 
         ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.0.b");
-        ASSERT_FALSE(execInfo.inPlace); // TODO turn in-place on for this.
         ASSERT_FALSE(execInfo.noOp);
 
         Document logDoc;