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diff --git a/src/mongo/util/queue.h b/src/mongo/util/queue.h
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+// @file queue.h
+
+/*    Copyright 2009 10gen Inc.
+ *
+ *    Licensed under the Apache License, Version 2.0 (the "License");
+ *    you may not use this file except in compliance with the License.
+ *    You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ */
+
+#pragma once
+
+#include "mongo/pch.h"
+
+#include <limits>
+#include <queue>
+
+#include "mongo/util/timer.h"
+
+namespace mongo {
+
+    template <typename T>
+    size_t _getSizeDefault(const T& t) {
+        return 1;
+    }
+
+    /**
+     * Simple blocking queue with optional max size.
+     * A custom sizing function can optionally be given.  By default, size is calculated as
+     * _queue.size().
+     */
+    template<typename T>
+    class BlockingQueue : boost::noncopyable {
+        typedef size_t (*getSizeFunc)(const T& t);
+    public:
+        BlockingQueue() :
+            _lock("BlockingQueue"),
+            _maxSize(std::numeric_limits<std::size_t>::max()),
+            _currentSize(0),
+            _getSize(&_getSizeDefault) {}
+        BlockingQueue(size_t size) :
+            _lock("BlockingQueue(bounded)"),
+            _maxSize(size),
+            _currentSize(0),
+            _getSize(&_getSizeDefault) {}
+        BlockingQueue(size_t size, getSizeFunc f) :
+            _lock("BlockingQueue(custom size)"),
+            _maxSize(size),
+            _currentSize(0),
+            _getSize(f) {}
+
+        void push(T const& t) {
+            scoped_lock l( _lock );
+            size_t tSize = _getSize(t);
+            while (_queue.size()+tSize >= _maxSize) {
+                _cvNoLongerFull.wait( l.boost() );
+            }
+            _queue.push( t );
+            _currentSize += tSize;
+            _cvNoLongerEmpty.notify_one();
+        }
+
+        bool empty() const {
+            scoped_lock l( _lock );
+            return _queue.empty();
+        }
+
+        size_t size() const {
+            scoped_lock l( _lock );
+            return _currentSize;
+        }
+
+        void clear() {
+            scoped_lock l(_lock);
+            _queue = std::queue<T>();
+            _currentSize = 0;
+        }
+
+        bool tryPop( T & t ) {
+            scoped_lock l( _lock );
+            if ( _queue.empty() )
+                return false;
+
+            t = _queue.front();
+            _queue.pop();
+            _currentSize -= _getSize(t);
+            _cvNoLongerFull.notify_one();
+
+            return true;
+        }
+
+        T blockingPop() {
+
+            scoped_lock l( _lock );
+            while( _queue.empty() )
+                _cvNoLongerEmpty.wait( l.boost() );
+
+            T t = _queue.front();
+            _queue.pop();
+            _currentSize -= _getSize(t);
+            _cvNoLongerFull.notify_one();
+
+            return t;
+        }
+
+
+        /**
+         * blocks waiting for an object until maxSecondsToWait passes
+         * if got one, return true and set in t
+         * otherwise return false and t won't be changed
+         */
+        bool blockingPop( T& t , int maxSecondsToWait ) {
+
+            Timer timer;
+
+            boost::xtime xt;
+            boost::xtime_get(&xt, MONGO_BOOST_TIME_UTC);
+            xt.sec += maxSecondsToWait;
+
+            scoped_lock l( _lock );
+            while( _queue.empty() ) {
+                if ( ! _cvNoLongerEmpty.timed_wait( l.boost() , xt ) )
+                    return false;
+            }
+
+            t = _queue.front();
+            _queue.pop();
+            _currentSize -= _getSize(t);
+            _cvNoLongerFull.notify_one();
+            return true;
+        }
+
+        // Obviously, this should only be used when you have
+        // only one consumer
+        bool blockingPeek(T& t, int maxSecondsToWait) {
+            Timer timer;
+
+            boost::xtime xt;
+            boost::xtime_get(&xt, MONGO_BOOST_TIME_UTC);
+            xt.sec += maxSecondsToWait;
+
+            scoped_lock l( _lock );
+            while( _queue.empty() ) {
+                if ( ! _cvNoLongerEmpty.timed_wait( l.boost() , xt ) )
+                    return false;
+            }
+
+            t = _queue.front();
+            return true;
+        }
+
+        // Obviously, this should only be used when you have
+        // only one consumer
+        bool peek(T& t) {
+
+            scoped_lock l( _lock );
+            if (_queue.empty()) {
+                return false;
+            }
+
+            t = _queue.front();
+            return true;
+        }
+
+    private:
+        mutable mongo::mutex _lock;
+        std::queue<T> _queue;
+        const size_t _maxSize;
+        size_t _currentSize;
+        getSizeFunc _getSize;
+
+        boost::condition _cvNoLongerFull;
+        boost::condition _cvNoLongerEmpty;
+    };
+
+}