SERVER-14041 enhance secondaryThrottle parameter

19 files changed, 359 insertions, 69 deletions

diff --git a/src/mongo/db/commands/cleanup_orphaned_cmd.cpp b/src/mongo/db/commands/cleanup_orphaned_cmd.cpp
index 89e7f49ab4b..3fd6dbcb9d2 100644
--- a/src/mongo/db/commands/cleanup_orphaned_cmd.cpp
+++ b/src/mongo/db/commands/cleanup_orphaned_cmd.cpp
@@ -41,11 +41,22 @@
 #include "mongo/db/jsobj.h"
 #include "mongo/db/namespace_string.h"
 #include "mongo/db/range_deleter_service.h"
+#include "mongo/db/repl/repl_coordinator_global.h"
 #include "mongo/s/collection_metadata.h"
 #include "mongo/s/d_logic.h"
 #include "mongo/s/range_arithmetic.h"
+#include "mongo/s/type_settings.h"
 #include "mongo/util/log.h"
 
+namespace {
+    using mongo::WriteConcernOptions;
+
+    const int kDefaultWTimeoutMs = 60 * 1000;
+    const WriteConcernOptions DefaultWriteConcern("majority",
+                                                  WriteConcernOptions::NONE,
+                                                  kDefaultWTimeoutMs);
+}
+
 namespace mongo {
 
     MONGO_LOG_DEFAULT_COMPONENT_FILE(::mongo::logger::LogComponent::kCommands);
@@ -69,7 +80,7 @@ namespace mongo {
     CleanupResult cleanupOrphanedData( OperationContext* txn,
                                        const NamespaceString& ns,
                                        const BSONObj& startingFromKeyConst,
-                                       bool secondaryThrottle,
+                                       const WriteConcernOptions& secondaryThrottle,
                                        BSONObj* stoppedAtKey,
                                        string* errMsg ) {
 
@@ -153,6 +164,17 @@ namespace mongo {
      * the balancer is off.
      *
      * Safe to call with the balancer on.
+     *
+     * Format:
+     *
+     * {
+     *      cleanupOrphaned: <ns>,
+     *      // optional parameters:
+     *      startingAtKey: { <shardKeyValue> }, // defaults to lowest value
+     *      secondaryThrottle: <bool>, // defaults to true
+     *      // defaults to { w: "majority", wtimeout: 60000 }. Applies to individual writes.
+     *      writeConcern: { <writeConcern options> }
+     * }
      */
     class CleanupOrphanedCommand : public Command {
     public:
@@ -179,7 +201,6 @@ namespace mongo {
         // Input
         static BSONField<string> nsField;
         static BSONField<BSONObj> startingFromKeyField;
-        static BSONField<bool> secondaryThrottleField;
 
         // Output
         static BSONField<BSONObj> stoppedAtKeyField;
@@ -210,12 +231,29 @@ namespace mongo {
                 return false;
             }
 
-            bool secondaryThrottle = true;
-            if ( !FieldParser::extract( cmdObj,
-                                        secondaryThrottleField,
-                                        &secondaryThrottle,
-                                        &errmsg ) ) {
-                return false;
+            WriteConcernOptions writeConcern;
+            Status status = writeConcern.parseSecondaryThrottle(cmdObj, NULL);
+
+            if (!status.isOK()){
+                if (status.code() != ErrorCodes::WriteConcernNotDefined) {
+                    return appendCommandStatus(result, status);
+                }
+
+                writeConcern = DefaultWriteConcern;
+            }
+            else {
+                repl::ReplicationCoordinator* replCoordinator =
+                        repl::getGlobalReplicationCoordinator();
+                Status status = replCoordinator->checkIfWriteConcernCanBeSatisfied(writeConcern);
+                if (!status.isOK()) {
+                    return appendCommandStatus(result, status);
+                }
+            }
+
+            if (writeConcern.shouldWaitForOtherNodes() &&
+                    writeConcern.wTimeout == WriteConcernOptions::kNoTimeout) {
+                // Don't allow no timeout.
+                writeConcern.wTimeout = kDefaultWTimeoutMs;
             }
 
             if (!shardingState.enabled()) {
@@ -225,7 +263,7 @@ namespace mongo {
             }
 
             ChunkVersion shardVersion;
-            Status status = shardingState.refreshMetadataNow( ns, &shardVersion );
+            status = shardingState.refreshMetadataNow( ns, &shardVersion );
             if ( !status.isOK() ) {
                 if ( status.code() == ErrorCodes::RemoteChangeDetected ) {
                     warning() << "Shard version in transition detected while refreshing "
@@ -242,7 +280,7 @@ namespace mongo {
             CleanupResult cleanupResult = cleanupOrphanedData( txn,
                                                                NamespaceString( ns ),
                                                                startingFromKey,
-                                                               secondaryThrottle,
+                                                               writeConcern,
                                                                &stoppedAtKey,
                                                                &errmsg );
 
@@ -263,7 +301,6 @@ namespace mongo {
 
     BSONField<string> CleanupOrphanedCommand::nsField( "cleanupOrphaned" );
     BSONField<BSONObj> CleanupOrphanedCommand::startingFromKeyField( "startingFromKey" );
-    BSONField<bool> CleanupOrphanedCommand::secondaryThrottleField( "secondaryThrottle" );
     BSONField<BSONObj> CleanupOrphanedCommand::stoppedAtKeyField( "stoppedAtKey" );
 
     MONGO_INITIALIZER(RegisterCleanupOrphanedCommand)(InitializerContext* context) {
diff --git a/src/mongo/db/dbhelpers.cpp b/src/mongo/db/dbhelpers.cpp
index 83b5b0b7ec5..8cc0eb0bd1c 100644
--- a/src/mongo/db/dbhelpers.cpp
+++ b/src/mongo/db/dbhelpers.cpp
@@ -52,6 +52,7 @@
 #include "mongo/db/repl/oplog.h"
 #include "mongo/db/repl/repl_coordinator_global.h"
 #include "mongo/db/write_concern.h"
+#include "mongo/db/write_concern_options.h"
 #include "mongo/db/operation_context_impl.h"
 #include "mongo/db/storage_options.h"
 #include "mongo/db/catalog/collection.h"
@@ -305,7 +306,7 @@ namespace mongo {
     long long Helpers::removeRange( OperationContext* txn,
                                     const KeyRange& range,
                                     bool maxInclusive,
-                                    bool secondaryThrottle,
+                                    const WriteConcernOptions& writeConcern,
                                     RemoveSaver* callback,
                                     bool fromMigrate,
                                     bool onlyRemoveOrphanedDocs )
@@ -342,7 +343,7 @@ namespace mongo {
                 Helpers::toKeyFormat( indexKeyPattern.extendRangeBound(range.maxKey,maxInclusive));
 
         LOG(1) << "begin removal of " << min << " to " << max << " in " << ns
-               << (secondaryThrottle ? " (waiting for secondaries)" : "" ) << endl;
+               << " with write concern: " << writeConcern.toBSON() << endl;
 
         Client& c = cc();
 
@@ -435,10 +436,7 @@ namespace mongo {
             // TODO remove once the yielding below that references this timer has been removed
             Timer secondaryThrottleTime;
 
-            if ( secondaryThrottle && numDeleted > 0 ) {
-                WriteConcernOptions writeConcern;
-                writeConcern.wNumNodes = 2;
-                writeConcern.wTimeout = 60 * 1000;
+            if (writeConcern.shouldWaitForOtherNodes() && numDeleted > 0) {
                 repl::ReplicationCoordinator::StatusAndDuration replStatus =
                         repl::getGlobalReplicationCoordinator()->awaitReplication(txn,
                                                                                   c.getLastOp(),
@@ -454,7 +452,7 @@ namespace mongo {
             }
         }
         
-        if ( secondaryThrottle )
+        if (writeConcern.shouldWaitForOtherNodes())
             log() << "Helpers::removeRangeUnlocked time spent waiting for replication: "  
                   << millisWaitingForReplication << "ms" << endl;
         
diff --git a/src/mongo/db/dbhelpers.h b/src/mongo/db/dbhelpers.h
index be0ca859248..865543c74f9 100644
--- a/src/mongo/db/dbhelpers.h
+++ b/src/mongo/db/dbhelpers.h
@@ -41,6 +41,7 @@ namespace mongo {
     class Collection;
     class Cursor;
     class OperationContext;
+    struct WriteConcernOptions;
 
     /**
      * db helpers are helper functions and classes that let us easily manipulate the local
@@ -164,8 +165,8 @@ namespace mongo {
          */
         static long long removeRange( OperationContext* txn,
                                       const KeyRange& range,
-                                      bool maxInclusive = false,
-                                      bool secondaryThrottle = false,
+                                      bool maxInclusive,
+                                      const WriteConcernOptions& secondaryThrottle,
                                       RemoveSaver* callback = NULL,
                                       bool fromMigrate = false,
                                       bool onlyRemoveOrphanedDocs = false );
diff --git a/src/mongo/db/field_parser.cpp b/src/mongo/db/field_parser.cpp
index 40c8c9664eb..47b5b8cf1c0 100644
--- a/src/mongo/db/field_parser.cpp
+++ b/src/mongo/db/field_parser.cpp
@@ -111,7 +111,7 @@ namespace mongo {
     {
         if (elem.eoo()) {
             if (field.hasDefault()) {
-                *out = field.getDefault();
+                *out = field.getDefault().getOwned();
                 return FIELD_DEFAULT;
             }
             else {
diff --git a/src/mongo/db/range_deleter.cpp b/src/mongo/db/range_deleter.cpp
index d096cab1219..e75ce96f0bd 100644
--- a/src/mongo/db/range_deleter.cpp
+++ b/src/mongo/db/range_deleter.cpp
@@ -189,7 +189,7 @@ namespace mongo {
                                    const BSONObj& min,
                                    const BSONObj& max,
                                    const BSONObj& shardKeyPattern,
-                                   bool secondaryThrottle,
+                                   const WriteConcernOptions& writeConcern,
                                    Notification* notifyDone,
                                    std::string* errMsg) {
         string dummy;
@@ -199,7 +199,7 @@ namespace mongo {
                                                                  min.getOwned(),
                                                                  max.getOwned(),
                                                                  shardKeyPattern.getOwned(),
-                                                                 secondaryThrottle));
+                                                                 writeConcern));
         toDelete->notifyDone = notifyDone;
 
         {
@@ -243,10 +243,13 @@ namespace mongo {
     }
 
 namespace {
-    bool _waitForReplication(OperationContext* txn, std::string* errMsg) {
-        WriteConcernOptions writeConcern;
-        writeConcern.wMode = "majority";
-        writeConcern.wTimeout = 60 * 60 * 1000;
+    const int kWTimeoutMillis = 60 * 60 * 1000;
+
+    bool _waitForMajority(OperationContext* txn, std::string* errMsg) {
+        const WriteConcernOptions writeConcern("majority",
+                                               WriteConcernOptions::NONE,
+                                               kWTimeoutMillis);
+
         repl::ReplicationCoordinator::StatusAndDuration replStatus =
                 repl::getGlobalReplicationCoordinator()->awaitReplicationOfLastOp(txn,
                                                                                   writeConcern);
@@ -279,7 +282,7 @@ namespace {
                                  const BSONObj& min,
                                  const BSONObj& max,
                                  const BSONObj& shardKeyPattern,
-                                 bool secondaryThrottle,
+                                 const WriteConcernOptions& writeConcern,
                                  string* errMsg) {
         if (stopRequested()) {
             *errMsg = "deleter is already stopped.";
@@ -314,7 +317,7 @@ namespace {
                   << " cursors in " << ns << " to finish" << endl;
         }
 
-        RangeDeleteEntry taskDetails(ns, min, max, shardKeyPattern, secondaryThrottle);
+        RangeDeleteEntry taskDetails(ns, min, max, shardKeyPattern, writeConcern);
         taskDetails.stats.queueStartTS = jsTime();
 
         Date_t timeSinceLastLog;
@@ -373,7 +376,7 @@ namespace {
 
         if (result) {
             taskDetails.stats.waitForReplStartTS = jsTime();
-            result = _waitForReplication(txn, errMsg);
+            result = _waitForMajority(txn, errMsg);
             taskDetails.stats.waitForReplEndTS = jsTime();
         }
 
@@ -555,7 +558,7 @@ namespace {
                 if (delResult) {
                     nextTask->stats.waitForReplStartTS = jsTime();
 
-                    if (!_waitForReplication(txn.get(), &errMsg)) {
+                    if (!_waitForMajority(txn.get(), &errMsg)) {
                         warning() << "Error encountered while waiting for replication: " << errMsg;
                     }
 
@@ -662,12 +665,12 @@ namespace {
                                        const BSONObj& min,
                                        const BSONObj& max,
                                        const BSONObj& shardKey,
-                                       bool secondaryThrottle):
+                                       const WriteConcernOptions& writeConcern):
                                                ns(ns),
                                                min(min),
                                                max(max),
                                                shardKeyPattern(shardKey),
-                                               secondaryThrottle(secondaryThrottle),
+                                               writeConcern(writeConcern),
                                                notifyDone(NULL) {
     }
 
diff --git a/src/mongo/db/range_deleter.h b/src/mongo/db/range_deleter.h
index 022f3c84872..cda4578b02b 100644
--- a/src/mongo/db/range_deleter.h
+++ b/src/mongo/db/range_deleter.h
@@ -39,6 +39,7 @@
 #include "mongo/db/clientcursor.h"
 #include "mongo/db/jsobj.h"
 #include "mongo/db/operation_context.h"
+#include "mongo/db/write_concern_options.h"
 #include "mongo/util/concurrency/mutex.h"
 #include "mongo/util/concurrency/synchronization.h"
 #include "mongo/util/time_support.h"
@@ -138,7 +139,7 @@ namespace mongo {
                          const BSONObj& min,
                          const BSONObj& max,
                          const BSONObj& shardKeyPattern,
-                         bool secondaryThrottle,
+                         const WriteConcernOptions& writeConcern,
                          Notification* notifyDone,
                          std::string* errMsg);
 
@@ -154,7 +155,7 @@ namespace mongo {
                        const BSONObj& min,
                        const BSONObj& max,
                        const BSONObj& shardKeyPattern,
-                       bool secondaryThrottle,
+                       const WriteConcernOptions& writeConcern,
                        std::string* errMsg);
 
         /**
@@ -309,7 +310,7 @@ namespace mongo {
                          const BSONObj& min,
                          const BSONObj& max,
                          const BSONObj& shardKey,
-                         bool secondaryThrottle);
+                         const WriteConcernOptions& writeConcern);
 
         const std::string ns;
 
@@ -324,7 +325,7 @@ namespace mongo {
         // like hash indexes.
         const BSONObj shardKeyPattern;
 
-        const bool secondaryThrottle;
+        const WriteConcernOptions writeConcern;
 
         // Sets of cursors to wait to close until this can be ready
         // for deletion.
diff --git a/src/mongo/db/range_deleter_db_env.cpp b/src/mongo/db/range_deleter_db_env.cpp
index 3658f99cd2c..29e96e4ead4 100644
--- a/src/mongo/db/range_deleter_db_env.cpp
+++ b/src/mongo/db/range_deleter_db_env.cpp
@@ -63,7 +63,7 @@ namespace mongo {
         const BSONObj inclusiveLower(taskDetails.min);
         const BSONObj exclusiveUpper(taskDetails.max);
         const BSONObj keyPattern(taskDetails.shardKeyPattern);
-        const bool secondaryThrottle(taskDetails.secondaryThrottle);
+        const WriteConcernOptions writeConcern(taskDetails.writeConcern);
 
         const bool initiallyHaveClient = haveClient();
 
@@ -85,8 +85,6 @@ namespace mongo {
                   << endl;
 
             try {
-                bool throttle = repl::getGlobalReplicationCoordinator()->getReplicationMode() ==
-                        repl::ReplicationCoordinator::modeReplSet ? secondaryThrottle : false;
                 *deletedDocs =
                         Helpers::removeRange(txn,
                                              KeyRange(ns,
@@ -94,7 +92,7 @@ namespace mongo {
                                                       exclusiveUpper,
                                                       keyPattern),
                                              false, /*maxInclusive*/
-                                             throttle,
+                                             writeConcern,
                                              serverGlobalParams.moveParanoia ? &removeSaver : NULL,
                                              true, /*fromMigrate*/
                                              true); /*onlyRemoveOrphans*/
diff --git a/src/mongo/db/range_deleter_test.cpp b/src/mongo/db/range_deleter_test.cpp
index 05ce3918320..c0b50aee619 100644
--- a/src/mongo/db/range_deleter_test.cpp
+++ b/src/mongo/db/range_deleter_test.cpp
@@ -35,6 +35,7 @@
 #include "mongo/db/repl/repl_coordinator_global.h"
 #include "mongo/db/repl/repl_coordinator_mock.h"
 #include "mongo/db/repl/repl_settings.h"
+#include "mongo/db/write_concern_options.h"
 #include "mongo/stdx/functional.h"
 #include "mongo/unittest/unittest.h"
 
@@ -57,6 +58,7 @@ namespace {
     const int MAX_IMMEDIATE_DELETE_WAIT_SECS = 2;
 
     const mongo::repl::ReplSettings replSettings;
+    const mongo::WriteConcernOptions dummyWriteConcern;
 
     // Should not be able to queue deletes if deleter workers were not started.
     TEST(QueueDelete, CantAfterStop) {
@@ -73,7 +75,7 @@ namespace {
                                          BSON("x" << 120),
                                          BSON("x" << 200),
                                          BSON("x" << 1),
-                                         true,
+                                         dummyWriteConcern,
                                          NULL /* notifier not needed */,
                                          &errMsg));
         ASSERT_FALSE(errMsg.empty());
@@ -93,8 +95,13 @@ namespace {
         env->addCursorId(ns, 345);
 
         Notification notifyDone;
-        ASSERT_TRUE(deleter.queueDelete(ns, BSON("x" << 0), BSON("x" << 10), BSON("x" << 1),
-                                        true, &notifyDone, NULL /* errMsg not needed */));
+        ASSERT_TRUE(deleter.queueDelete(ns,
+                                        BSON("x" << 0),
+                                        BSON("x" << 10),
+                                        BSON("x" << 1),
+                                        dummyWriteConcern,
+                                        &notifyDone,
+                                        NULL /* errMsg not needed */));
 
         env->waitForNthGetCursor(1u);
 
@@ -129,8 +136,13 @@ namespace {
         env->addCursorId(ns, 345);
 
         Notification notifyDone;
-        ASSERT_TRUE(deleter.queueDelete(ns, BSON("x" << 0), BSON("x" << 10),  BSON("x" << 1),
-                                        true, &notifyDone, NULL /* errMsg not needed */));
+        ASSERT_TRUE(deleter.queueDelete(ns,
+                                        BSON("x" << 0),
+                                        BSON("x" << 10),
+                                        BSON("x" << 1),
+                                        dummyWriteConcern,
+                                        &notifyDone,
+                                        NULL /* errMsg not needed */));
 
 
         env->waitForNthGetCursor(1u);
@@ -145,9 +157,9 @@ namespace {
                                       const BSONObj& min,
                                       const BSONObj& max,
                                       const BSONObj& shardKeyPattern,
-                                      bool secondaryThrottle,
+                                      const mongo::WriteConcernOptions& secondaryThrottle,
                                       std::string* errMsg) {
-        deleter->deleteNow(txn, ns, min, max, shardKeyPattern, secondaryThrottle, errMsg);
+        deleter->deleteNow(txn,ns, min, max, shardKeyPattern, secondaryThrottle, errMsg);
     }
 
     // Should not start delete if the set of cursors that were open when the
@@ -171,7 +183,7 @@ namespace {
                                                             BSON("x" << 0),
                                                             BSON("x" << 10),
                                                             BSON("x" << 1),
-                                                            true,
+                                                            dummyWriteConcern,
                                                             &errMsg));
 
         env->waitForNthGetCursor(1u);
@@ -220,7 +232,7 @@ namespace {
                                                             BSON("x" << 0),
                                                             BSON("x" << 10),
                                                             BSON("x" << 1),
-                                                            true,
+                                                            dummyWriteConcern,
                                                             &errMsg));
 
         env->waitForNthGetCursor(1u);
@@ -262,7 +274,7 @@ namespace {
                                         BSON("x" << 10),
                                         BSON("x" << 20),
                                         BSON("x" << 1),
-                                        true,
+                                        dummyWriteConcern,
                                         &notifyDone1,
                                         NULL /* don't care errMsg */));
 
@@ -276,7 +288,7 @@ namespace {
                                         BSON("x" << 20),
                                         BSON("x" << 30),
                                         BSON("x" << 1),
-                                        true,
+                                        dummyWriteConcern,
                                         &notifyDone2,
                                         NULL /* don't care errMsg */));
 
@@ -285,7 +297,7 @@ namespace {
                                         BSON("x" << 30),
                                         BSON("x" << 40),
                                         BSON("x" << 1),
-                                        true,
+                                        dummyWriteConcern,
                                         &notifyDone3,
                                         NULL /* don't care errMsg */));
 
@@ -358,13 +370,23 @@ namespace {
         ASSERT_TRUE(errMsg.empty());
 
         errMsg.clear();
-        ASSERT_FALSE(deleter.queueDelete(ns, BSON("x" << 120), BSON("x" << 140),  BSON("x" << 1),
-                                         false, NULL /* notifier not needed */, &errMsg));
+        ASSERT_FALSE(deleter.queueDelete(ns,
+                                         BSON("x" << 120),
+                                         BSON("x" << 140),
+                                         BSON("x" << 1),
+                                         dummyWriteConcern,
+                                         NULL /* notifier not needed */,
+                                         &errMsg));
         ASSERT_FALSE(errMsg.empty());
 
         errMsg.clear();
-        ASSERT_FALSE(deleter.deleteNow(noTxn, ns, BSON("x" << 120), BSON("x" << 140),
-                                       BSON("x" << 1), false, &errMsg));
+        ASSERT_FALSE(deleter.deleteNow(noTxn,
+                                       ns,
+                                       BSON("x" << 120),
+                                       BSON("x" << 140),
+                                       BSON("x" << 1),
+                                       dummyWriteConcern,
+                                       &errMsg));
         ASSERT_FALSE(errMsg.empty());
 
         ASSERT_FALSE(env->deleteOccured());
@@ -410,8 +432,13 @@ namespace {
         env->addCursorId(ns, 58);
 
         Notification notifyDone;
-        deleter.queueDelete(ns, BSON("x" << 0), BSON("x" << 10), BSON("x" << 1),
-                            false, &notifyDone, NULL /* errMsg not needed */);
+        deleter.queueDelete(ns,
+                            BSON("x" << 0),
+                            BSON("x" << 10),
+                            BSON("x" << 1),
+                            dummyWriteConcern,
+                            &notifyDone,
+                            NULL /* errMsg not needed */);
 
         string errMsg;
         ASSERT_FALSE(deleter.addToBlackList(ns, BSON("x" << 5), BSON("x" << 15), &errMsg));
@@ -448,7 +475,7 @@ namespace {
                                                             BSON("x" << 64),
                                                             BSON("x" << 70),
                                                             BSON("x" << 1),
-                                                            true,
+                                                            dummyWriteConcern,
                                                             &delErrMsg));
 
         env->waitForNthPausedDelete(1u);
@@ -484,8 +511,13 @@ namespace {
         ASSERT_FALSE(deleter.removeFromBlackList(ns, BSON("x" << 1234), BSON("x" << 9000)));
 
         // Range should still be blacklisted
-        ASSERT_FALSE(deleter.deleteNow(noTxn, ns, BSON("x" << 2000), BSON("x" << 4000), BSON("x" << 1),
-                                       false, NULL /* errMsg not needed */));
+        ASSERT_FALSE(deleter.deleteNow(noTxn,
+                                       ns,
+                                       BSON("x" << 2000),
+                                       BSON("x" << 4000),
+                                       BSON("x" << 1),
+                                       dummyWriteConcern,
+                                       NULL /* errMsg not needed */));
 
         deleter.stopWorkers();
     }
@@ -503,15 +535,25 @@ namespace {
         ASSERT_TRUE(errMsg.empty());
 
         errMsg.clear();
-        ASSERT_FALSE(deleter.deleteNow(noTxn, ns, BSON("x" << 600), BSON("x" << 700),
-                                       BSON("x" << 1), false, &errMsg));
+        ASSERT_FALSE(deleter.deleteNow(noTxn,
+                                       ns,
+                                       BSON("x" << 600),
+                                       BSON("x" << 700),
+                                       BSON("x" << 1),
+                                       dummyWriteConcern,
+                                       &errMsg));
         ASSERT_FALSE(errMsg.empty());
 
         ASSERT_TRUE(deleter.removeFromBlackList(ns, BSON("x" << 500), BSON("x" << 801)));
 
         errMsg.clear();
-        ASSERT_TRUE(deleter.deleteNow(noTxn, ns, BSON("x" << 600), BSON("x" << 700),
-                                      BSON("x" << 1), false, &errMsg));
+        ASSERT_TRUE(deleter.deleteNow(noTxn,
+                                      ns,
+                                      BSON("x" << 600),
+                                      BSON("x" << 700),
+                                      BSON("x" << 1),
+                                      dummyWriteConcern,
+                                      &errMsg));
         ASSERT_TRUE(errMsg.empty());
 
         deleter.stopWorkers();
@@ -527,8 +569,13 @@ namespace {
         deleter.addToBlackList("foo.bar", BSON("x" << 100), BSON("x" << 200),
                                NULL /* errMsg not needed */);
 
-        ASSERT_TRUE(deleter.deleteNow(noTxn, "test.user", BSON("x" << 120), BSON("x" << 140),
-                                      BSON("x" << 1), true, NULL /* errMsg not needed */));
+        ASSERT_TRUE(deleter.deleteNow(noTxn,
+                                      "test.user",
+                                      BSON("x" << 120),
+                                      BSON("x" << 140),
+                                      BSON("x" << 1),
+                                      dummyWriteConcern,
+                                      NULL /* errMsg not needed */));
 
         deleter.stopWorkers();
     }
diff --git a/src/mongo/db/repl/repl_coordinator.h b/src/mongo/db/repl/repl_coordinator.h
index cf9b20630e6..000476fd4e8 100644
--- a/src/mongo/db/repl/repl_coordinator.h
+++ b/src/mongo/db/repl/repl_coordinator.h
@@ -201,6 +201,17 @@ namespace repl {
         virtual bool canAcceptWritesForDatabase(const StringData& dbName) = 0;
 
         /**
+         * Checks if the current replica set configuration can satisfy the given write concern.
+         *
+         * Things that are taken into consideration include:
+         * 1. If the set has enough members.
+         * 2. If the tag exists.
+         * 3. If there are enough members for the tag specified.
+         */
+        virtual Status checkIfWriteConcernCanBeSatisfied(
+                const WriteConcernOptions& writeConcern) const = 0;
+
+        /*
          * Returns Status::OK() if it is valid for this node to serve reads on the given collection
          * and an errorcode indicating why the node cannot if it cannot.
          */
diff --git a/src/mongo/db/repl/repl_coordinator_hybrid.cpp b/src/mongo/db/repl/repl_coordinator_hybrid.cpp
index c065008e033..7ca34597f20 100644
--- a/src/mongo/db/repl/repl_coordinator_hybrid.cpp
+++ b/src/mongo/db/repl/repl_coordinator_hybrid.cpp
@@ -275,5 +275,12 @@ namespace repl {
         return legacyResponse;
     }
 
+    Status HybridReplicationCoordinator::checkIfWriteConcernCanBeSatisfied(
+            const WriteConcernOptions& writeConcern) const {
+        Status legacyStatus = _legacy.checkIfWriteConcernCanBeSatisfied(writeConcern);
+        Status implStatus = _impl.checkIfWriteConcernCanBeSatisfied(writeConcern);
+        return legacyStatus;
+    }
+
 } // namespace repl
 } // namespace mongo
diff --git a/src/mongo/db/repl/repl_coordinator_hybrid.h b/src/mongo/db/repl/repl_coordinator_hybrid.h
index 8a339e556d5..bf375e0a0ee 100644
--- a/src/mongo/db/repl/repl_coordinator_hybrid.h
+++ b/src/mongo/db/repl/repl_coordinator_hybrid.h
@@ -83,6 +83,9 @@ namespace repl {
 
         virtual bool canAcceptWritesForDatabase(const StringData& dbName);
 
+        virtual Status checkIfWriteConcernCanBeSatisfied(
+                        const WriteConcernOptions& writeConcern) const;
+
         virtual Status canServeReadsFor(const NamespaceString& ns, bool slaveOk);
 
         virtual bool shouldIgnoreUniqueIndex(const IndexDescriptor* idx);
diff --git a/src/mongo/db/repl/repl_coordinator_impl.cpp b/src/mongo/db/repl/repl_coordinator_impl.cpp
index 9949b10a673..5da1a1deb39 100644
--- a/src/mongo/db/repl/repl_coordinator_impl.cpp
+++ b/src/mongo/db/repl/repl_coordinator_impl.cpp
@@ -446,5 +446,12 @@ namespace repl {
         // TODO
         return std::vector<BSONObj>();
     }
+
+    Status ReplicationCoordinatorImpl::checkIfWriteConcernCanBeSatisfied(
+            const WriteConcernOptions& writeConcern) const {
+        // TODO
+        return Status::OK();
+    }
+
 } // namespace repl
 } // namespace mongo
diff --git a/src/mongo/db/repl/repl_coordinator_impl.h b/src/mongo/db/repl/repl_coordinator_impl.h
index 095c3897a70..62e043f9d0c 100644
--- a/src/mongo/db/repl/repl_coordinator_impl.h
+++ b/src/mongo/db/repl/repl_coordinator_impl.h
@@ -89,6 +89,9 @@ namespace repl {
 
         virtual bool canAcceptWritesForDatabase(const StringData& database);
 
+        virtual Status checkIfWriteConcernCanBeSatisfied(
+                const WriteConcernOptions& writeConcern) const;
+
         virtual Status canServeReadsFor(const NamespaceString& ns, bool slaveOk);
 
         virtual bool shouldIgnoreUniqueIndex(const IndexDescriptor* idx);
diff --git a/src/mongo/db/repl/repl_coordinator_legacy.cpp b/src/mongo/db/repl/repl_coordinator_legacy.cpp
index f4be0d26369..17c30dfb9e0 100644
--- a/src/mongo/db/repl/repl_coordinator_legacy.cpp
+++ b/src/mongo/db/repl/repl_coordinator_legacy.cpp
@@ -944,5 +944,19 @@ namespace {
         return repl::getHostsWrittenTo(op);
     }
 
+    Status LegacyReplicationCoordinator::checkIfWriteConcernCanBeSatisfied(
+            const WriteConcernOptions& writeConcern) const {
+        // TODO: rewrite this method with the correct version. Note that this just a
+        // temporary stub for secondary throttle.
+
+        if (getReplicationMode() == ReplicationCoordinator::modeReplSet) {
+            if (writeConcern.wNumNodes > 1 && theReplSet->config().getMajority() <= 1) {
+                return Status(ErrorCodes::CannotSatisfyWriteConcern, "not enough nodes");
+            }
+        }
+
+        return Status::OK();
+    }
+
 } // namespace repl
 } // namespace mongo
diff --git a/src/mongo/db/repl/repl_coordinator_legacy.h b/src/mongo/db/repl/repl_coordinator_legacy.h
index a9095f80a09..f9cf15be96c 100644
--- a/src/mongo/db/repl/repl_coordinator_legacy.h
+++ b/src/mongo/db/repl/repl_coordinator_legacy.h
@@ -79,6 +79,9 @@ namespace repl {
 
         virtual bool canAcceptWritesForDatabase(const StringData& dbName);
 
+        virtual Status checkIfWriteConcernCanBeSatisfied(
+                const WriteConcernOptions& writeConcern) const;
+
         virtual Status canServeReadsFor(const NamespaceString& ns, bool slaveOk);
 
         virtual bool shouldIgnoreUniqueIndex(const IndexDescriptor* idx);
diff --git a/src/mongo/db/repl/repl_coordinator_mock.cpp b/src/mongo/db/repl/repl_coordinator_mock.cpp
index b7b712bd0d4..aab04be4938 100644
--- a/src/mongo/db/repl/repl_coordinator_mock.cpp
+++ b/src/mongo/db/repl/repl_coordinator_mock.cpp
@@ -223,5 +223,11 @@ namespace repl {
         // TODO
         return std::vector<BSONObj>();
     }
+
+    Status ReplicationCoordinatorMock::checkIfWriteConcernCanBeSatisfied(
+            const WriteConcernOptions& writeConcern) const {
+        return Status::OK();
+    }
+
 } // namespace repl
 } // namespace mongo
diff --git a/src/mongo/db/repl/repl_coordinator_mock.h b/src/mongo/db/repl/repl_coordinator_mock.h
index 260ed685705..1ac42d4a248 100644
--- a/src/mongo/db/repl/repl_coordinator_mock.h
+++ b/src/mongo/db/repl/repl_coordinator_mock.h
@@ -82,6 +82,9 @@ namespace repl {
 
         virtual bool canAcceptWritesForDatabase(const StringData& dbName);
 
+        virtual Status checkIfWriteConcernCanBeSatisfied(
+                const WriteConcernOptions& writeConcern) const;
+
         virtual Status canServeReadsFor(const NamespaceString& ns, bool slaveOk);
 
         virtual bool shouldIgnoreUniqueIndex(const IndexDescriptor* idx);
diff --git a/src/mongo/db/write_concern_options.cpp b/src/mongo/db/write_concern_options.cpp
index 848c4e4464c..90690b87599 100644
--- a/src/mongo/db/write_concern_options.cpp
+++ b/src/mongo/db/write_concern_options.cpp
@@ -27,7 +27,9 @@
 
 #include "mongo/db/write_concern_options.h"
 
+#include "mongo/bson/bson_field.h"
 #include "mongo/client/dbclientinterface.h"
+#include "mongo/db/field_parser.h"
 
 namespace mongo {
 
@@ -36,6 +38,27 @@ namespace mongo {
     const BSONObj WriteConcernOptions::AllConfigs = BSONObj();
     const BSONObj WriteConcernOptions::Unacknowledged(BSON("w" << W_NONE));
 
+    static const BSONField<bool> mongosSecondaryThrottleField("_secondaryThrottle", true);
+    static const BSONField<bool> secondaryThrottleField("secondaryThrottle", true);
+    static const BSONField<BSONObj> writeConcernField("writeConcern");
+
+    WriteConcernOptions::WriteConcernOptions(int numNodes,
+                                             SyncMode sync,
+                                             int timeout):
+                            syncMode(sync),
+                            wNumNodes(numNodes),
+                            wTimeout(timeout) {
+    }
+
+    WriteConcernOptions::WriteConcernOptions(const std::string& mode,
+                                             SyncMode sync,
+                                             int timeout):
+                            syncMode(sync),
+                            wNumNodes(0),
+                            wMode(mode),
+                            wTimeout(timeout) {
+    }
+
     Status WriteConcernOptions::parse( const BSONObj& obj ) {
         if ( obj.isEmpty() ) {
             return Status( ErrorCodes::FailedToParse, "write concern object cannot be empty" );
@@ -86,4 +109,84 @@ namespace mongo {
 
         return Status::OK();
     }
+
+    Status WriteConcernOptions::parseSecondaryThrottle(const BSONObj& doc,
+                                                       BSONObj* rawWriteConcernObj) {
+        string errMsg;
+        bool isSecondaryThrottle;
+        FieldParser::FieldState fieldState = FieldParser::extract(doc,
+                                                                  secondaryThrottleField,
+                                                                  &isSecondaryThrottle,
+                                                                  &errMsg);
+        if (fieldState == FieldParser::FIELD_INVALID) {
+            return Status(ErrorCodes::FailedToParse, errMsg);
+        }
+
+        if (fieldState != FieldParser::FIELD_SET) {
+            fieldState = FieldParser::extract(doc,
+                                              mongosSecondaryThrottleField,
+                                              &isSecondaryThrottle,
+                                              &errMsg);
+
+            if (fieldState == FieldParser::FIELD_INVALID) {
+                return Status(ErrorCodes::FailedToParse, errMsg);
+            }
+        }
+
+        BSONObj dummyBSON;
+        if (!rawWriteConcernObj) {
+            rawWriteConcernObj = &dummyBSON;
+        }
+
+        fieldState = FieldParser::extract(doc,
+                                          writeConcernField,
+                                          rawWriteConcernObj,
+                                          &errMsg);
+        if (fieldState == FieldParser::FIELD_INVALID) {
+            return Status(ErrorCodes::FailedToParse, errMsg);
+        }
+
+        if (!isSecondaryThrottle) {
+            if (!rawWriteConcernObj->isEmpty()) {
+                return Status(ErrorCodes::UnsupportedFormat,
+                              "Cannot have write concern when secondary throttle is false");
+            }
+
+            wNumNodes = 1;
+            return Status::OK();
+        }
+
+        if (rawWriteConcernObj->isEmpty()) {
+            return Status(ErrorCodes::WriteConcernNotDefined,
+                          "Secondary throttle is on, but write concern is not specified");
+        }
+
+        return parse(*rawWriteConcernObj);
+    }
+
+    BSONObj WriteConcernOptions::toBSON() const {
+        BSONObjBuilder builder;
+
+        if (wMode.empty()) {
+            builder.append("w", wNumNodes);
+        }
+        else {
+            builder.append("w", wMode);
+        }
+
+        if (syncMode == FSYNC) {
+            builder.append("fsync", true);
+        }
+        else if (syncMode == JOURNAL) {
+            builder.append("j", true);
+        }
+
+        builder.append("wtimeout", wTimeout);
+
+        return builder.obj();
+    }
+
+    bool WriteConcernOptions::shouldWaitForOtherNodes() const {
+        return !wMode.empty() || wNumNodes > 1;
+    }
 }
diff --git a/src/mongo/db/write_concern_options.h b/src/mongo/db/write_concern_options.h
index 44c67b2938b..31b0f556c30 100644
--- a/src/mongo/db/write_concern_options.h
+++ b/src/mongo/db/write_concern_options.h
@@ -37,8 +37,11 @@ namespace mongo {
     struct WriteConcernOptions {
     public:
 
+        enum SyncMode { NONE, FSYNC, JOURNAL };
+
         static const int kNoTimeout = 0;
         static const int kNoWaiting = -1;
+
         static const BSONObj Default;
         static const BSONObj Acknowledged;
         static const BSONObj AllConfigs;
@@ -46,8 +49,43 @@ namespace mongo {
 
         WriteConcernOptions() { reset(); }
 
+        WriteConcernOptions(int numNodes,
+                            SyncMode sync,
+                            int timeout);
+
+        WriteConcernOptions(const std::string& mode,
+                            SyncMode sync,
+                            int timeout);
+
         Status parse( const BSONObj& obj );
 
+        /**
+         * Extracts the write concern settings from the BSONObj. The BSON object should have
+         * the format:
+         *
+         * {
+         *     ...
+         *     secondaryThrottle: <bool>, // optional
+         *     _secondaryThrottle: <bool>, // optional
+         *     writeConcern: <BSONObj> // optional
+         * }
+         *
+         * Note: secondaryThrottle takes precedence over _secondaryThrottle.
+         *
+         * Also sets output parameter rawWriteConcernObj if the writeCocnern field exists.
+         *
+         * Returns OK if the parse was successful. Also returns ErrorCodes::WriteConcernNotDefined
+         * when secondary throttle is true but write concern was not specified.
+         */
+        Status parseSecondaryThrottle(const BSONObj& doc,
+                                      BSONObj* rawWriteConcernObj);
+
+        /**
+         * Return true if the server needs to wait for other secondary nodes to satisfy this
+         * write concern setting. Errs on the false positive for non-empty wMode.
+         */
+        bool shouldWaitForOtherNodes() const;
+
         void reset() {
             syncMode = NONE;
             wNumNodes = 0;
@@ -55,11 +93,18 @@ namespace mongo {
             wTimeout = 0;
         }
 
-        enum SyncMode { NONE, FSYNC, JOURNAL } syncMode;
+        // Returns the BSON representation of this object.
+        // Warning: does not return the same object passed on the last parse() call.
+        BSONObj toBSON() const;
+
+        SyncMode syncMode;
 
+        // The w parameter for this write concern. The wMode represents the string format and
+        // takes precedence over the numeric format wNumNodes.
         int wNumNodes;
         std::string wMode;
 
+        // Timeout in milliseconds.
         int wTimeout;
     };