diff --git a/src/mongo/db/stats/counters.cpp b/src/mongo/db/stats/counters.cpp
index 5b67e22..85ac08b 100644
--- a/src/mongo/db/stats/counters.cpp
+++ b/src/mongo/db/stats/counters.cpp
@@ -139,30 +139,24 @@ void NetworkCounter::hit(long long bytesIn, long long bytesOut) {
     const long long MAX = 1ULL << 60;
 
     // don't care about the race as its just a counter
-    bool overflow = _bytesIn > MAX || _bytesOut > MAX;
+    bool overflow = _bytesIn.loadRelaxed() > MAX || _bytesOut.loadRelaxed() > MAX;
 
     if (overflow) {
-        _lock.lock();
-        _overflows++;
-        _bytesIn = bytesIn;
-        _bytesOut = bytesOut;
-        _requests = 1;
-        _lock.unlock();
+        _overflows.fetchAndAdd(1);
+        _bytesIn.fetchAndAdd(bytesIn);
+        _bytesOut.fetchAndAdd(bytesOut);
+        _requests.store(1);
     } else {
-        _lock.lock();
-        _bytesIn += bytesIn;
-        _bytesOut += bytesOut;
-        _requests++;
-        _lock.unlock();
+        _bytesIn.fetchAndAdd(bytesIn);
+        _bytesOut.fetchAndAdd(bytesOut);
+        _requests.fetchAndAdd(1);
     }
 }
 
 void NetworkCounter::append(BSONObjBuilder& b) {
-    _lock.lock();
-    b.appendNumber("bytesIn", _bytesIn);
-    b.appendNumber("bytesOut", _bytesOut);
-    b.appendNumber("numRequests", _requests);
-    _lock.unlock();
+    b.append("bytesIn", (long long)_bytesIn.loadRelaxed());
+    b.append("bytesOut", (long long)_bytesOut.loadRelaxed());
+    b.append("numRequests", (long long)_requests.loadRelaxed());
 }
 
 
diff --git a/src/mongo/db/stats/counters.h b/src/mongo/db/stats/counters.h
index 1821f7b..5aa568b 100644
--- a/src/mongo/db/stats/counters.h
+++ b/src/mongo/db/stats/counters.h
@@ -100,13 +100,11 @@ public:
     void append(BSONObjBuilder& b);
 
 private:
-    long long _bytesIn;
-    long long _bytesOut;
-    long long _requests;
+    AtomicUInt64 _bytesIn;
+    AtomicUInt64 _bytesOut;
+    AtomicUInt64 _requests;
 
-    long long _overflows;
-
-    SpinLock _lock;
+    AtomicUInt64 _overflows;
 };
 
 extern NetworkCounter networkCounter;