Exemplo n.º 1
0
 void BtreeBasedBuilder::addKeysToPhaseOne(NamespaceDetails* d, const char* ns,
                        const IndexDetails& idx,
                        const BSONObj& order,
                        SortPhaseOne* phaseOne,
                        int64_t nrecords,
                        ProgressMeter* progressMeter,
                        bool mayInterrupt, int idxNo) {
     shared_ptr<Cursor> cursor = theDataFileMgr.findAll( ns );
     phaseOne->sortCmp.reset(getComparison(idx.version(), idx.keyPattern()));
     phaseOne->sorter.reset(new BSONObjExternalSorter(phaseOne->sortCmp.get()));
     phaseOne->sorter->hintNumObjects( nrecords );
     auto_ptr<IndexDescriptor> desc(CatalogHack::getDescriptor(d, idxNo));
     auto_ptr<BtreeBasedAccessMethod> iam(CatalogHack::getBtreeBasedIndex(desc.get()));
     while ( cursor->ok() ) {
         RARELY killCurrentOp.checkForInterrupt( !mayInterrupt );
         BSONObj o = cursor->current();
         DiskLoc loc = cursor->currLoc();
         BSONObjSet keys;
         iam->getKeys(o, &keys);
         phaseOne->addKeys(keys, loc, mayInterrupt);
         cursor->advance();
         progressMeter->hit();
         if ( logLevel > 1 && phaseOne->n % 10000 == 0 ) {
             printMemInfo( "\t iterating objects" );
         }
     }
 }
Exemplo n.º 2
0
    void IndexChanges::dupCheck(IndexDetails& idx, DiskLoc curObjLoc) {
        if (added.empty() || 
            !idx.unique() || 
            ignoreUniqueIndex(idx)) {
            return;
        }
        const Ordering ordering = Ordering::make(idx.keyPattern());

        // "E11001 duplicate key on update"
        idx.idxInterface().uassertIfDups(idx, added, idx.head, curObjLoc, ordering);
    }
Exemplo n.º 3
0
 DiskLoc BtreeBasedBuilder::makeEmptyIndex(const IndexDetails& idx) {
     if (0 == idx.version()) {
         return BtreeBucket<V0>::addBucket(idx);
     } else {
         return BtreeBucket<V1>::addBucket(idx);
     }
 }
Exemplo n.º 4
0
 BtreeCursor::BtreeCursor( NamespaceDetails *_d, int _idxNo, const IndexDetails &_id,
                           const BSONObj &_startKey, const BSONObj &_endKey, bool endKeyInclusive, int _direction ) :
     d(_d), idxNo(_idxNo),
     startKey( _startKey ),
     endKey( _endKey ),
     _endKeyInclusive( endKeyInclusive ),
     _multikey( d->isMultikey( idxNo ) ),
     indexDetails( _id ),
     _order( _id.keyPattern() ),
     _ordering( Ordering::make( _order ) ),
     _direction( _direction ),
     _spec( _id.getSpec() ),
     _independentFieldRanges( false ),
     _nscanned( 0 ) {
     audit();
 }
Exemplo n.º 5
0
    // throws DBException
    void buildAnIndex(const std::string& ns,
                      NamespaceDetails* d,
                      IndexDetails& idx,
                      bool mayInterrupt) {

        BSONObj idxInfo = idx.info.obj();

        MONGO_TLOG(0) << "build index on: " << ns << " properties: " << idxInfo.jsonString() << endl;

        audit::logCreateIndex( currentClient.get(), &idxInfo, idx.indexName(), ns );

        Timer t;
        unsigned long long n;

        verify( Lock::isWriteLocked(ns) );

        if( inDBRepair || !idxInfo["background"].trueValue() ) {
            int idxNo = d->findIndexByName( idx.info.obj()["name"].valuestr(), true );
            verify( idxNo >= 0 );
            n = BtreeBasedBuilder::fastBuildIndex(ns.c_str(), d, idx, mayInterrupt, idxNo);
            verify( !idx.head.isNull() );
        }
        else {
            BackgroundIndexBuildJob j(ns.c_str());
            n = j.go(ns, d, idx);
        }
        MONGO_TLOG(0) << "build index done.  scanned " << n << " total records. " << t.millis() / 1000.0 << " secs" << endl;
    }
Exemplo n.º 6
0
    BtreeCursor::BtreeCursor( const IndexDetails &_id, const BSONObj &_startKey, const BSONObj &_endKey, int _direction ) :
    startKey( _startKey ),
    endKey( _endKey ),
    indexDetails( _id ),
    order( _id.keyPattern() ),
    direction( _direction ) {
        bool found;
        if ( otherTraceLevel >= 12 ) {
            if ( otherTraceLevel >= 200 ) {
                out() << "::BtreeCursor() qtl>200.  validating entire index." << endl;
                indexDetails.head.btree()->fullValidate(indexDetails.head, order);
            }
            else {
                out() << "BTreeCursor(). dumping head bucket" << endl;
                indexDetails.head.btree()->dump();
            }
        }

        bucket = indexDetails.head.btree()->
        locate(indexDetails, indexDetails.head, startKey, order, keyOfs, found, direction > 0 ? minDiskLoc : maxDiskLoc, direction);
        
        skipUnusedKeys();
        
        checkEnd();         
    }
Exemplo n.º 7
0
 // static
 DiskLoc QueryRunner::fastFindSingle(const IndexDetails &indexdetails, const BSONObj& key) {
     const int version = indexdetails.version();
     if (0 == version) {
         return indexdetails.head.btree<V0>()->findSingle(indexdetails, indexdetails.head, key);
     } else {
         verify(1 == version);
         return indexdetails.head.btree<V1>()->findSingle(indexdetails, indexdetails.head, key);
     }
 }
Exemplo n.º 8
0
 BtreeCursor::BtreeCursor( NamespaceDetails *_d, int _idxNo, const IndexDetails& _id, const shared_ptr< FieldRangeVector > &_bounds, int _direction, bool useFRVSpec )
     :
     d(_d), idxNo(_idxNo),
     _endKeyInclusive( true ),
     _multikey( d->isMultikey( idxNo ) ),
     indexDetails( _id ),
     _order( _id.keyPattern() ),
     _ordering( Ordering::make( _order ) ),
     _direction( _direction ),
     _bounds( ( assert( _bounds.get() ), _bounds ) ),
     _boundsIterator( new FieldRangeVectorIterator( *_bounds  ) ),
     _spec( useFRVSpec ? _bounds->getSpec() : _id.getSpec() ),
     _independentFieldRanges( true ),
     _nscanned( 0 ) {
     massert( 13384, "BtreeCursor FieldRangeVector constructor doesn't accept special indexes", !_spec.getType() );
     audit();
     startKey = _bounds->startKey();
     _boundsIterator->advance( startKey ); // handles initialization
     _boundsIterator->prepDive();
     bucket = indexDetails.head;
     keyOfs = 0;
 }
Exemplo n.º 9
0
 virtual void uassertIfDups(IndexDetails& idx, vector<BSONObj*>& addedKeys, DiskLoc head, DiskLoc self, const Ordering& ordering) { 
     const BtreeBucket<V> *h = head.btree<V>();
     for( vector<BSONObj*>::iterator i = addedKeys.begin(); i != addedKeys.end(); i++ ) {
         KeyOwned k(**i);
         bool dup = h->wouldCreateDup(idx, head, k, ordering, self);
         if (dup) {
             stringstream ss;
             ss << "E11001 duplicate key on update error ";
             ss << "index: " << idx.indexNamespace() << "  ";
             ss << "dup key: " << k.toString();
             uasserted(11001, ss.str());
         }
     }
 }
Exemplo n.º 10
0
 BtreeCursor::BtreeCursor( NamespaceDetails *_d, int _idxNo, const IndexDetails &_id, 
                           const BSONObj &_startKey, const BSONObj &_endKey, bool endKeyInclusive, int _direction ) :
         d(_d), idxNo(_idxNo), 
         startKey( _startKey ),
         endKey( _endKey ),
         endKeyInclusive_( endKeyInclusive ),
         multikey( d->isMultikey( idxNo ) ),
         indexDetails( _id ),
         order( _id.keyPattern() ),
         direction( _direction ),
         boundIndex_()
 {
     audit();
     init();
 }
Exemplo n.º 11
0
 BtreeCursor::BtreeCursor( NamespaceDetails *_d, int _idxNo, const IndexDetails& _id, const shared_ptr< FieldRangeVector > &_bounds, int _direction )
     :
         d(_d), idxNo(_idxNo), 
         endKeyInclusive_( true ),
         multikey( d->isMultikey( idxNo ) ),
         indexDetails( _id ),
         order( _id.keyPattern() ),
         _ordering( Ordering::make( order ) ),
         direction( _direction ),
         bounds_( ( assert( _bounds.get() ), _bounds ) ),
         _boundsIterator( new FieldRangeVector::Iterator( *bounds_  ) ),
         _spec( _id.getSpec() ),
         _independentFieldRanges( true )
 {
     massert( 13384, "BtreeCursor FieldRangeVector constructor doesn't accept special indexes", !_spec.getType() );
     audit();
     startKey = bounds_->startKey();
     bool found;
     _boundsIterator->advance( startKey ); // handles initialization
     bucket = indexDetails.head.btree()->
     locate(indexDetails, indexDetails.head, startKey, _ordering, keyOfs, found, direction > 0 ? minDiskLoc : maxDiskLoc, direction);
     skipAndCheck();
     DEV assert( dups.size() == 0 );
 }
Exemplo n.º 12
0
 BtreeCursor::BtreeCursor( NamespaceDetails *_d, int _idxNo, const IndexDetails& _id, const vector< pair< BSONObj, BSONObj > > &_bounds, int _direction )
     :
         d(_d), idxNo(_idxNo), 
         endKeyInclusive_( true ),
         multikey( d->isMultikey( idxNo ) ),
         indexDetails( _id ),
         order( _id.keyPattern() ),
         direction( _direction ),
         bounds_( _bounds ),
         boundIndex_()
 {
     assert( !bounds_.empty() );
     startKey = bounds_[ 0 ].first;
     endKey = bounds_[ 0 ].second;
     audit();
     init();
 }
Exemplo n.º 13
0
        unsigned long long go(string ns, NamespaceDetails *d, IndexDetails& idx, int idxNo) {
            unsigned long long n = 0;

            prep(ns.c_str(), d);
            verify( idxNo == d->nIndexes );
            try {
                idx.head.writing() = idx.idxInterface().addBucket(idx);
                n = addExistingToIndex(ns.c_str(), d, idx, idxNo);
            }
            catch(...) {
                if( cc().database() && nsdetails(ns.c_str()) == d ) {
                    verify( idxNo == d->nIndexes );
                    done(ns.c_str(), d);
                }
                else {
                    log() << "ERROR: db gone during bg index?" << endl;
                }
                throw;
            }
            verify( idxNo == d->nIndexes );
            done(ns.c_str(), d);
            return n;
        }
Exemplo n.º 14
0
    uint64_t BtreeBasedBuilder::fastBuildIndex(const char* ns, NamespaceDetails* d,
                                               IndexDetails& idx, bool mayInterrupt,
                                               int idxNo) {
        CurOp * op = cc().curop();

        Timer t;

        tlog(1) << "fastBuildIndex " << ns << ' ' << idx.info.obj().toString() << endl;

        bool dupsAllowed = !idx.unique() || ignoreUniqueIndex(idx);
        bool dropDups = idx.dropDups() || inDBRepair;
        BSONObj order = idx.keyPattern();

        getDur().writingDiskLoc(idx.head).Null();

        if ( logLevel > 1 ) printMemInfo( "before index start" );

        /* get and sort all the keys ----- */
        ProgressMeterHolder pm(op->setMessage("index: (1/3) external sort",
                                              "Index: (1/3) External Sort Progress",
                                              d->stats.nrecords,
                                              10));
        SortPhaseOne phase1;
        addKeysToPhaseOne(d, ns, idx, order, &phase1, d->stats.nrecords, pm.get(),
                          mayInterrupt, idxNo );
        pm.finished();

        BSONObjExternalSorter& sorter = *(phase1.sorter);

        if( phase1.multi ) {
            d->setIndexIsMultikey(ns, idxNo);
        }

        if ( logLevel > 1 ) printMemInfo( "before final sort" );
        phase1.sorter->sort( mayInterrupt );
        if ( logLevel > 1 ) printMemInfo( "after final sort" );

        LOG(t.seconds() > 5 ? 0 : 1) << "\t external sort used : " << sorter.numFiles()
                                     << " files " << " in " << t.seconds() << " secs" << endl;

        set<DiskLoc> dupsToDrop;

        /* build index --- */
        if( idx.version() == 0 )
            buildBottomUpPhases2And3<V0>(dupsAllowed,
                                         idx,
                                         sorter,
                                         dropDups,
                                         dupsToDrop,
                                         op,
                                         &phase1,
                                         pm,
                                         t,
                                         mayInterrupt);
        else if( idx.version() == 1 ) 
            buildBottomUpPhases2And3<V1>(dupsAllowed,
                                         idx,
                                         sorter,
                                         dropDups,
                                         dupsToDrop,
                                         op,
                                         &phase1,
                                         pm,
                                         t,
                                         mayInterrupt);
        else
            verify(false);

        if( dropDups ) 
            log() << "\t fastBuildIndex dupsToDrop:" << dupsToDrop.size() << endl;

        BtreeBasedBuilder::doDropDups(ns, d, dupsToDrop, mayInterrupt);

        return phase1.n;
    }
Exemplo n.º 15
0
    bool run2DSphereGeoNear(const IndexDetails &id, BSONObj& cmdObj, string& errmsg,
                            BSONObjBuilder& result) {
        S2IndexType *idxType = static_cast<S2IndexType*>(id.getSpec().getType());
        verify(&id == idxType->getDetails());

        // We support both "num" and "limit" options to control limit
        int numWanted = 100;
        const char* limitName = cmdObj["num"].isNumber() ? "num" : "limit";
        if (cmdObj[limitName].isNumber()) {
            numWanted = cmdObj[limitName].numberInt();
            verify(numWanted >= 0);
        }

        // Don't count any docs twice.  Isn't this default behavior?  Or will yields screw this up?
        //bool uniqueDocs = false;
        //if (!cmdObj["uniqueDocs"].eoo()) uniqueDocs = cmdObj["uniqueDocs"].trueValue();

        // Add the location information to each result as a field with name 'loc'.
        bool includeLocs = false;
        if (!cmdObj["includeLocs"].eoo()) includeLocs = cmdObj["includeLocs"].trueValue();

        // The actual query point
        uassert(16551, "'near' param missing/invalid", !cmdObj["near"].eoo());
        BSONObj nearObj = cmdObj["near"].embeddedObject();

        // nearObj must be a point.
        uassert(16571, "near must be called with a point, called with " + nearObj.toString(),
                GeoParser::isPoint(nearObj));

        // The non-near query part.
        BSONObj query;
        if (cmdObj["query"].isABSONObj())
            query = cmdObj["query"].embeddedObject();

        // The farthest away we're willing to look.
        double maxDistance = numeric_limits<double>::max();
        if (cmdObj["maxDistance"].isNumber())
            maxDistance = cmdObj["maxDistance"].number();

        vector<string> geoFieldNames;
        idxType->getGeoFieldNames(&geoFieldNames);
        uassert(16552, "geoNear called but no indexed geo fields?", 1 == geoFieldNames.size());
        QueryGeometry queryGeo(geoFieldNames[0]);
        uassert(16553, "geoNear couldn't parse geo: " + nearObj.toString(), queryGeo.parseFrom(nearObj));
        vector<QueryGeometry> regions;
        regions.push_back(queryGeo);

        scoped_ptr<S2NearCursor> cursor(new S2NearCursor(idxType->keyPattern(), idxType->getDetails(),
                                                         query, regions, idxType->getParams(),
                                                         numWanted, maxDistance));

        double totalDistance = 0;
        int results = 0;
        BSONObjBuilder resultBuilder(result.subarrayStart("results"));
        double farthestDist = 0;

        while (cursor->ok()) {
            double dist = cursor->currentDistance();
            totalDistance += dist;
            if (dist > farthestDist) { farthestDist = dist; }

            BSONObjBuilder oneResultBuilder(resultBuilder.subobjStart(BSONObjBuilder::numStr(results)));
            oneResultBuilder.append("dis", dist);
            if (includeLocs) {
                BSONElementSet geoFieldElements;
                cursor->current().getFieldsDotted(geoFieldNames[0], geoFieldElements, false);
                for (BSONElementSet::iterator oi = geoFieldElements.begin();
                        oi != geoFieldElements.end(); ++oi) {
                    if (oi->isABSONObj()) {
                        oneResultBuilder.appendAs(*oi, "loc");
                    }
                }
            }

            oneResultBuilder.append("obj", cursor->current());
            oneResultBuilder.done();
            ++results;
            cursor->advance();
        }

        resultBuilder.done();

        BSONObjBuilder stats(result.subobjStart("stats"));
        stats.append("time", cc().curop()->elapsedMillis());
        stats.appendNumber("nscanned", cursor->nscanned());
        stats.append("avgDistance", totalDistance / results);
        stats.append("maxDistance", farthestDist);
        stats.done();

        return true;
    }
Exemplo n.º 16
0
        unsigned long long addExistingToIndex(const char *ns, NamespaceDetails *d, IndexDetails& idx, int idxNo) {
            bool dupsAllowed = !idx.unique();
            bool dropDups = idx.dropDups();

            ProgressMeter& progress = cc().curop()->setMessage( "bg index build" , d->stats.nrecords );

            unsigned long long n = 0;
            unsigned long long numDropped = 0;
            auto_ptr<ClientCursor> cc;
            {
                shared_ptr<Cursor> c = theDataFileMgr.findAll(ns);
                cc.reset( new ClientCursor(QueryOption_NoCursorTimeout, c, ns) );
            }

            while ( cc->ok() ) {
                BSONObj js = cc->current();
                try {
                    {
                        if ( !dupsAllowed && dropDups ) {
                            LastError::Disabled led( lastError.get() );
                            addKeysToIndex(ns, d, idxNo, js, cc->currLoc(), dupsAllowed);
                        }
                        else {
                            addKeysToIndex(ns, d, idxNo, js, cc->currLoc(), dupsAllowed);
                        }
                    }
                    cc->advance();
                }
                catch( AssertionException& e ) {
                    if( e.interrupted() ) {
                        killCurrentOp.checkForInterrupt();
                    }

                    if ( dropDups ) {
                        DiskLoc toDelete = cc->currLoc();
                        bool ok = cc->advance();
                        ClientCursor::YieldData yieldData;
                        massert( 16093, "after yield cursor deleted" , cc->prepareToYield( yieldData ) );
                        theDataFileMgr.deleteRecord( ns, toDelete.rec(), toDelete, false, true , true );
                        if( !cc->recoverFromYield( yieldData ) ) {
                            cc.release();
                            if( !ok ) {
                                /* we were already at the end. normal. */
                            }
                            else {
                                uasserted(12585, "cursor gone during bg index; dropDups");
                            }
                            break;
                        }
                        numDropped++;
                    }
                    else {
                        log() << "background addExistingToIndex exception " << e.what() << endl;
                        throw;
                    }
                }
                n++;
                progress.hit();

                getDur().commitIfNeeded();

                if ( cc->yieldSometimes( ClientCursor::WillNeed ) ) {
                    progress.setTotalWhileRunning( d->stats.nrecords );
                }
                else {
                    cc.release();
                    uasserted(12584, "cursor gone during bg index");
                    break;
                }
            }
            progress.finished();
            if ( dropDups )
                log() << "\t backgroundIndexBuild dupsToDrop: " << numDropped << endl;
            return n;
        }
Exemplo n.º 17
0
    // throws DBException
    unsigned long long fastBuildIndex(const char *ns, NamespaceDetails *d, IndexDetails& idx, int idxNo) {
        CurOp * op = cc().curop();

        Timer t;

        tlog(1) << "fastBuildIndex " << ns << " idxNo:" << idxNo << ' ' << idx.info.obj().toString() << endl;

        bool dupsAllowed = !idx.unique();
        bool dropDups = idx.dropDups() || inDBRepair;
        BSONObj order = idx.keyPattern();

        getDur().writingDiskLoc(idx.head).Null();

        if ( logLevel > 1 ) printMemInfo( "before index start" );

        /* get and sort all the keys ----- */
        ProgressMeterHolder pm( op->setMessage( "index: (1/3) external sort" , d->stats.nrecords , 10 ) );
        SortPhaseOne _ours;
        SortPhaseOne *phase1 = precalced;
        if( phase1 == 0 ) {
            phase1 = &_ours;
            SortPhaseOne& p1 = *phase1;
            shared_ptr<Cursor> c = theDataFileMgr.findAll(ns);
            p1.sorter.reset( new BSONObjExternalSorter(idx.idxInterface(), order) );
            p1.sorter->hintNumObjects( d->stats.nrecords );
            const IndexSpec& spec = idx.getSpec();
            while ( c->ok() ) {
                BSONObj o = c->current();
                DiskLoc loc = c->currLoc();
                p1.addKeys(spec, o, loc);
                c->advance();
                pm.hit();
                if ( logLevel > 1 && p1.n % 10000 == 0 ) {
                    printMemInfo( "\t iterating objects" );
                }
            };
        }
        pm.finished();

        BSONObjExternalSorter& sorter = *(phase1->sorter);

        if( phase1->multi )
            d->setIndexIsMultikey(ns, idxNo);

        if ( logLevel > 1 ) printMemInfo( "before final sort" );
        phase1->sorter->sort();
        if ( logLevel > 1 ) printMemInfo( "after final sort" );

        log(t.seconds() > 5 ? 0 : 1) << "\t external sort used : " << sorter.numFiles() << " files " << " in " << t.seconds() << " secs" << endl;

        set<DiskLoc> dupsToDrop;

        /* build index --- */
        if( idx.version() == 0 )
            buildBottomUpPhases2And3<V0>(dupsAllowed, idx, sorter, dropDups, dupsToDrop, op, phase1, pm, t);
        else if( idx.version() == 1 ) 
            buildBottomUpPhases2And3<V1>(dupsAllowed, idx, sorter, dropDups, dupsToDrop, op, phase1, pm, t);
        else
            verify(false);

        if( dropDups ) 
            log() << "\t fastBuildIndex dupsToDrop:" << dupsToDrop.size() << endl;

        for( set<DiskLoc>::iterator i = dupsToDrop.begin(); i != dupsToDrop.end(); i++ ){
            theDataFileMgr.deleteRecord( ns, i->rec(), *i, false /* cappedOk */ , true /* noWarn */ , isMaster( ns ) /* logOp */ );
            getDur().commitIfNeeded();
        }

        return phase1->n;
    }
Exemplo n.º 18
0
        unsigned long long addExistingToIndex(const char *ns, NamespaceDetails *d,
                                              IndexDetails& idx) {
            bool dupsAllowed = !idx.unique();
            bool dropDups = idx.dropDups();

            ProgressMeter& progress = cc().curop()->setMessage("bg index build",
                                                               "Background Index Build Progress",
                                                               d->numRecords());

            unsigned long long n = 0;
            unsigned long long numDropped = 0;

            auto_ptr<Runner> runner(InternalPlanner::collectionScan(ns));
            // We're not delegating yielding to the runner because we need to know when a yield
            // happens.
            RunnerYieldPolicy yieldPolicy;

            std::string idxName = idx.indexName();
            int idxNo = IndexBuildsInProgress::get(ns, idxName);

            // After this yields in the loop, idx may point at a different index (if indexes get
            // flipped, see insert_makeIndex) or even an empty IndexDetails, so nothing below should
            // depend on idx. idxNo should be recalculated after each yield.

            BSONObj js;
            DiskLoc loc;
            while (Runner::RUNNER_ADVANCED == runner->getNext(&js, &loc)) {
                try {
                    if ( !dupsAllowed && dropDups ) {
                        LastError::Disabled led( lastError.get() );
                        addKeysToIndex(ns, d, idxNo, js, loc, dupsAllowed);
                    }
                    else {
                        addKeysToIndex(ns, d, idxNo, js, loc, dupsAllowed);
                    }
                }
                catch( AssertionException& e ) {
                    if( e.interrupted() ) {
                        killCurrentOp.checkForInterrupt();
                    }

                    // TODO: Does exception really imply dropDups exception?
                    if (dropDups) {
                        bool runnerEOF = runner->isEOF();
                        runner->saveState();
                        theDataFileMgr.deleteRecord(d, ns, loc.rec(), loc, false, true, true);
                        if (!runner->restoreState()) {
                            // Runner got killed somehow.  This probably shouldn't happen.
                            if (runnerEOF) {
                                // Quote: "We were already at the end.  Normal.
                                // TODO: Why is this normal?
                            }
                            else {
                                uasserted(12585, "cursor gone during bg index; dropDups");
                            }
                            break;
                        }
                        // We deleted a record, but we didn't actually yield the dblock.
                        // TODO: Why did the old code assume we yielded the lock?
                        numDropped++;
                    }
                    else {
                        log() << "background addExistingToIndex exception " << e.what() << endl;
                        throw;
                    }
                }

                n++;
                progress.hit();

                getDur().commitIfNeeded();
                if (yieldPolicy.shouldYield()) {
                    if (!yieldPolicy.yieldAndCheckIfOK(runner.get())) {
                        uasserted(12584, "cursor gone during bg index");
                        break;
                    }

                    progress.setTotalWhileRunning( d->numRecords() );
                    // Recalculate idxNo if we yielded
                    idxNo = IndexBuildsInProgress::get(ns, idxName);
                }
            }

            progress.finished();
            if ( dropDups )
                log() << "\t backgroundIndexBuild dupsToDrop: " << numDropped << endl;
            return n;
        }