3 files changed, 13 insertions, 5 deletions
diff --git a/cpp/src/qpid/framing/FrameSet.cpp b/cpp/src/qpid/framing/FrameSet.cpp
index e6f15f2c4e..f5fe02c5ba 100644
--- a/cpp/src/qpid/framing/FrameSet.cpp
+++ b/cpp/src/qpid/framing/FrameSet.cpp
@@ -28,11 +28,12 @@
 using namespace qpid::framing;
 using namespace boost;
 
-FrameSet::FrameSet(const SequenceNumber& _id) : id(_id) {parts.reserve(4);}
+FrameSet::FrameSet(const SequenceNumber& _id) : id(_id),contentSize(0),recalculateSize(true) {parts.reserve(4);}
 
 void FrameSet::append(const AMQFrame& part)
 {
     parts.push_back(part);
+	recalculateSize = true;
 }
 
 bool FrameSet::isComplete() const
@@ -63,9 +64,14 @@ AMQHeaderBody* FrameSet::getHeaders()
 
 uint64_t FrameSet::getContentSize() const
 {
-    SumBodySize sum;
-    map_if(sum, TypeFilter<CONTENT_BODY>());
-    return sum.getSize();
+    if (recalculateSize)
+	{
+	    SumBodySize sum;
+        map_if(sum, TypeFilter<CONTENT_BODY>());
+        contentSize = sum.getSize();
+		recalculateSize = false;
+	}
+	return contentSize;
 }
 
 void FrameSet::getContent(std::string& out) const {
diff --git a/cpp/src/qpid/framing/FrameSet.h b/cpp/src/qpid/framing/FrameSet.h
index 454d292d9d..d23cb717c9 100644
--- a/cpp/src/qpid/framing/FrameSet.h
+++ b/cpp/src/qpid/framing/FrameSet.h
@@ -38,6 +38,8 @@ class FrameSet
     typedef std::vector<AMQFrame> Frames;
     const SequenceNumber id;
     Frames parts;
+	mutable uint64_t contentSize;
+	mutable bool recalculateSize;
 
 public:
     typedef boost::shared_ptr<FrameSet> shared_ptr;
diff --git a/cpp/src/tests/MessageBuilderTest.cpp b/cpp/src/tests/MessageBuilderTest.cpp
index 7149ec50c7..69e2ec1c1e 100644
--- a/cpp/src/tests/MessageBuilderTest.cpp
+++ b/cpp/src/tests/MessageBuilderTest.cpp
@@ -216,7 +216,7 @@ class MessageBuilderTest : public CppUnit::TestCase
         CPPUNIT_ASSERT(store.expectationsMet());
 
         //were the content frames dropped?
-        CPPUNIT_ASSERT_EQUAL((uint64_t) 0, builder.getMessage()->contentSize());
+        CPPUNIT_ASSERT(!builder.getMessage()->isContentLoaded());
     }
 };