diff --git a/primitives/primproc/batchprimitiveprocessor.cpp b/primitives/primproc/batchprimitiveprocessor.cpp
index 2fe026142..eb38f95fa 100644
--- a/primitives/primproc/batchprimitiveprocessor.cpp
+++ b/primitives/primproc/batchprimitiveprocessor.cpp
@@ -291,7 +291,7 @@ void BatchPrimitiveProcessor::initBPP(ByteStream& bs)
                 addToJoinerLocks[j].reset(new boost::mutex[processorThreads]);
 
             smallSideDataLocks.reset(new boost::mutex[joinerCount]);
-            tJoinerSizes.reset(new uint32_t[joinerCount]);
+            tJoinerSizes.reset(new atomic<uint32_t>[joinerCount]);
             largeSideKeyColumns.reset(new uint32_t[joinerCount]);
             tlLargeSideKeyColumns.reset(new vector<uint32_t>[joinerCount]);
             typelessJoin.reset(new bool[joinerCount]);
@@ -310,7 +310,10 @@ void BatchPrimitiveProcessor::initBPP(ByteStream& bs)
             for (i = 0; i < joinerCount; i++)
             {
                 doMatchNulls[i] = false;
-                bs >> tJoinerSizes[i];
+                uint32_t tmp32;
+                bs >> tmp32;
+                tJoinerSizes[i] = tmp32;
+                //bs >> tJoinerSizes[i];
                 //cout << "joiner size = " << tJoinerSizes[i] << endl;
                 bs >> joinTypes[i];
                 bs >> tmp8;
@@ -589,7 +592,7 @@ void BatchPrimitiveProcessor::addToJoiner(ByteStream& bs)
         idbassert(joinerNum < joinerCount);
         arr = (JoinerElements*) bs.buf();
 
-        uint32_t &tJoinerSize = tJoinerSizes[joinerNum];
+        atomic<uint32_t> &tJoinerSize = tJoinerSizes[joinerNum];
 
         // XXXPAT: enormous if stmts are evil.  TODO: move each block into
         // properly-named functions for clarity.
@@ -600,6 +603,7 @@ void BatchPrimitiveProcessor::addToJoiner(ByteStream& bs)
             uint8_t nullFlag;
             PoolAllocator &storedKeyAllocator = storedKeyAllocators[joinerNum];
             // this first loop hashes incoming values into vectors that parallel the hash tables.
+            uint nullCount = 0;
             for (i = 0; i < count; ++i)
             {
                 bs >> nullFlag;
@@ -611,8 +615,9 @@ void BatchPrimitiveProcessor::addToJoiner(ByteStream& bs)
                     tmpBuckets[bucket].push_back(make_pair(tlLargeKey, tlIndex));
                 }
                 else
-                    --tJoinerSize;
+                    ++nullCount;
             }
+            tJoinerSize -= nullCount;
 
             bool done = false, didSomeWork;
             //uint loopCounter = 0, noWorkCounter = 0;
diff --git a/primitives/primproc/batchprimitiveprocessor.h b/primitives/primproc/batchprimitiveprocessor.h
index 89402242c..e3863e429 100644
--- a/primitives/primproc/batchprimitiveprocessor.h
+++ b/primitives/primproc/batchprimitiveprocessor.h
@@ -284,7 +284,7 @@ private:
     typedef std::tr1::unordered_multimap<uint64_t, uint32_t,
             joiner::TupleJoiner::hasher, std::equal_to<uint64_t>,
             utils::STLPoolAllocator<std::pair<const uint64_t, uint32_t> > > TJoiner;
-            
+
     typedef std::tr1::unordered_multimap<joiner::TypelessData,
             uint32_t, joiner::TupleJoiner::hasher, std::equal_to<joiner::TypelessData>,
             utils::STLPoolAllocator<std::pair<const joiner::TypelessData, uint32_t> > > TLJoiner;
@@ -316,7 +316,7 @@ private:
     boost::shared_array<uint32_t> smallSideRowLengths;
     boost::shared_array<joblist::JoinType> joinTypes;
     uint32_t joinerCount;
-    boost::shared_array<uint32_t> tJoinerSizes;
+    boost::shared_array<std::atomic<uint32_t> > tJoinerSizes;
     // LSKC[i] = the column in outputRG joiner i uses as its key column
     boost::shared_array<uint32_t> largeSideKeyColumns;
     // KCPP[i] = true means a joiner uses projection step i as a key column
@@ -398,7 +398,7 @@ private:
     uint processorThreads;
     uint ptMask;
     bool firstInstance;
-    
+
     friend class Command;
     friend class ColumnCommand;
     friend class DictStep;
diff --git a/utils/common/poolallocator.cpp b/utils/common/poolallocator.cpp
index 5fdddce6d..da6f7d6c1 100644
--- a/utils/common/poolallocator.cpp
+++ b/utils/common/poolallocator.cpp
@@ -36,6 +36,7 @@ PoolAllocator& PoolAllocator::operator=(const PoolAllocator& v)
 {
     allocSize = v.allocSize;
     tmpSpace = v.tmpSpace;
+    useLock = v.useLock;
     deallocateAll();
     return *this;
 }
@@ -67,18 +68,28 @@ void PoolAllocator::newBlock()
 
 void * PoolAllocator::allocOOB(uint64_t size)
 {
+    bool _false = false;
     OOBMemInfo memInfo;
 
+    if (useLock)
+        while (!lock.compare_exchange_weak(_false, true, std::memory_order_acquire))
+            _false = false;
     memUsage += size;
     memInfo.mem.reset(new uint8_t[size]);
     memInfo.size = size;
     void *ret = (void*) memInfo.mem.get();
     oob[ret] = memInfo;
+    if (useLock)
+        lock.store(false, std::memory_order_release);
     return ret;
 }
-        
+
 void PoolAllocator::deallocate(void* p)
 {
+    bool _false = false;
+    if (useLock)
+        while (!lock.compare_exchange_weak(_false, true, std::memory_order_acquire))
+            _false = false;
     OutOfBandMap::iterator it = oob.find(p);
 
     if (it == oob.end())
@@ -86,6 +97,8 @@ void PoolAllocator::deallocate(void* p)
 
     memUsage -= it->second.size;
     oob.erase(it);
+    if (useLock)
+        lock.store(false, std::memory_order_release);
 }
 
 }