Add an extra indirection to the rarely used owned buffers, in order to keep the frequently accesed members in StructFieldValue close

3 files changed, 22 insertions, 13 deletions

diff --git a/document/src/tests/documenttestcase.cpp b/document/src/tests/documenttestcase.cpp
index 956f2d07e85..6993596392c 100644
--- a/document/src/tests/documenttestcase.cpp
+++ b/document/src/tests/documenttestcase.cpp
@@ -32,14 +32,14 @@ TEST(DocumentTest, testSizeOf)
 {
     EXPECT_EQ(24u, sizeof(std::vector<char>));
     EXPECT_EQ(24u, sizeof(vespalib::alloc::Alloc));
-    EXPECT_EQ(40u, sizeof(ByteBuffer));
+    EXPECT_EQ(24u, sizeof(ByteBuffer));
     EXPECT_EQ(32u, sizeof(vespalib::GrowableByteBuffer));
     EXPECT_EQ(88ul, sizeof(IdString));
     EXPECT_EQ(104ul, sizeof(DocumentId));
-    EXPECT_EQ(248ul, sizeof(Document));
-    EXPECT_EQ(112ul, sizeof(StructFieldValue));
+    EXPECT_EQ(232ul, sizeof(Document));
+    EXPECT_EQ(96ul, sizeof(StructFieldValue));
     EXPECT_EQ(16ul, sizeof(StructuredFieldValue));
-    EXPECT_EQ(72ul, sizeof(SerializableArray));
+    EXPECT_EQ(56ul, sizeof(SerializableArray));
 }
 
 TEST(DocumentTest, testFieldPath)
diff --git a/document/src/vespa/document/util/bytebuffer.cpp b/document/src/vespa/document/util/bytebuffer.cpp
index e1999c34288..bc7e726cb06 100644
--- a/document/src/vespa/document/util/bytebuffer.cpp
+++ b/document/src/vespa/document/util/bytebuffer.cpp
@@ -69,25 +69,33 @@ ByteBuffer::ByteBuffer(const char* buffer, uint32_t len) :
 {
 }
 
-ByteBuffer::ByteBuffer(Alloc buffer, uint32_t len) :
-      _buffer(static_cast<char *>(buffer.get())),
+ByteBuffer::ByteBuffer(Alloc buffer, uint32_t len)
+  : _buffer(static_cast<const char *>(buffer.get())),
+    _len(len),
+    _pos(0),
+    _ownedBuffer(std::make_unique<Alloc>(std::move(buffer)))
+{
+}
+
+ByteBuffer::ByteBuffer(std::unique_ptr<Alloc> buffer, uint32_t len)
+    : _buffer(static_cast<const char *>(buffer->get())),
       _len(len),
       _pos(0),
       _ownedBuffer(std::move(buffer))
 {
 }
 
-ByteBuffer::ByteBuffer(const ByteBuffer& rhs) :
-      _buffer(nullptr),
+ByteBuffer::ByteBuffer(const ByteBuffer& rhs)
+    : _buffer(nullptr),
       _len(rhs._len),
       _pos(rhs._pos),
       _ownedBuffer()
 {
     if (rhs._len > 0 && rhs._buffer) {
-        Alloc buf = Alloc::alloc(rhs._len);
+        auto buf = Alloc::alloc(rhs._len);
         memcpy(buf.get(), rhs._buffer, rhs._len);
-        _ownedBuffer = std::move(buf);
-        _buffer = static_cast<const char *>(_ownedBuffer.get());
+        _buffer = static_cast<const char *>(buf.get());
+        _ownedBuffer = std::make_unique<Alloc>(std::move(buf));
     }
 }
 
@@ -99,7 +107,7 @@ ByteBuffer::copyBuffer(const char* buffer, uint32_t len)
     if (buffer && len) {
         Alloc newBuf = Alloc::alloc(len);
         memcpy(newBuf.get(), buffer, len);
-        return ByteBuffer(std::move(newBuf), len);
+        return ByteBuffer(std::make_unique<Alloc>(std::move(newBuf)), len);
     } else {
         return ByteBuffer();
     }
diff --git a/document/src/vespa/document/util/bytebuffer.h b/document/src/vespa/document/util/bytebuffer.h
index 3f64f51a88a..1eb359e261b 100644
--- a/document/src/vespa/document/util/bytebuffer.h
+++ b/document/src/vespa/document/util/bytebuffer.h
@@ -46,6 +46,7 @@ public:
      * @param len The length of the buffer
      */
     ByteBuffer(vespalib::alloc::Alloc buffer, uint32_t len);
+    ByteBuffer(std::unique_ptr<vespalib::alloc::Alloc> buffer, uint32_t len);
 
     /**
      * Creates a ByteBuffer object from another buffer. allocates
@@ -113,7 +114,7 @@ private:
     const char *   _buffer;
     uint32_t       _len;
     uint32_t       _pos;
-    vespalib::alloc::Alloc _ownedBuffer;
+    std::unique_ptr<vespalib::alloc::Alloc> _ownedBuffer;
 };
 
 } // document