Merge pull request #15385 from vespa-engine/balder/reorder-for-smaller-footprint

Balder/reorder for smaller footprint

5 files changed, 139 insertions, 124 deletions

diff --git a/vespalib/src/tests/trace/trace.cpp b/vespalib/src/tests/trace/trace.cpp
index 92bee3231b0..992317b0289 100644
--- a/vespalib/src/tests/trace/trace.cpp
+++ b/vespalib/src/tests/trace/trace.cpp
@@ -146,25 +146,25 @@ TEST("testTraceLevel")
     t.setLevel(4);
     EXPECT_EQUAL(4u, t.getLevel());
     t.trace(9, "no");
-    EXPECT_EQUAL(0u, t.getRoot().getNumChildren());
+    EXPECT_EQUAL(0u, t.getNumChildren());
     t.trace(8, "no");
-    EXPECT_EQUAL(0u, t.getRoot().getNumChildren());
+    EXPECT_EQUAL(0u, t.getNumChildren());
     t.trace(7, "no");
-    EXPECT_EQUAL(0u, t.getRoot().getNumChildren());
+    EXPECT_EQUAL(0u, t.getNumChildren());
     t.trace(6, "no");
-    EXPECT_EQUAL(0u, t.getRoot().getNumChildren());
+    EXPECT_EQUAL(0u, t.getNumChildren());
     t.trace(5, "no");
-    EXPECT_EQUAL(0u, t.getRoot().getNumChildren());
+    EXPECT_EQUAL(0u, t.getNumChildren());
     t.trace(4, "yes");
-    EXPECT_EQUAL(1u, t.getRoot().getNumChildren());
+    EXPECT_EQUAL(1u, t.getNumChildren());
     t.trace(3, "yes");
-    EXPECT_EQUAL(2u, t.getRoot().getNumChildren());
+    EXPECT_EQUAL(2u, t.getNumChildren());
     t.trace(2, "yes");
-    EXPECT_EQUAL(3u, t.getRoot().getNumChildren());
+    EXPECT_EQUAL(3u, t.getNumChildren());
     t.trace(1, "yes");
-    EXPECT_EQUAL(4u, t.getRoot().getNumChildren());
+    EXPECT_EQUAL(4u, t.getNumChildren());
     t.trace(0, "yes");
-    EXPECT_EQUAL(5u, t.getRoot().getNumChildren());
+    EXPECT_EQUAL(5u, t.getNumChildren());
 }
 
 TEST("testCompact")
@@ -261,10 +261,10 @@ TEST("testTraceDump")
             b1.addChild(b2);
         }
         for (int i = 0; i < 10; ++i) {
-            big.getRoot().addChild(b1);
+            big.addChild(TraceNode(b1));
         }
         string normal = big.toString();
-        string full = big.getRoot().toString();
+        string full = big.toString(100000);
         EXPECT_GREATER(normal.size(), 30000u);
         EXPECT_LESS(normal.size(), 32000u);
         EXPECT_GREATER(full.size(), 50000u);
diff --git a/vespalib/src/vespa/vespalib/trace/trace.cpp b/vespalib/src/vespa/vespalib/trace/trace.cpp
index 8ca2ef6561c..be370aebbd2 100644
--- a/vespalib/src/vespa/vespalib/trace/trace.cpp
+++ b/vespalib/src/vespa/vespalib/trace/trace.cpp
@@ -6,43 +6,13 @@
 
 namespace vespalib {
 
-Trace::Trace() :
-    _level(0),
-    _root()
+Trace::Trace(const Trace &rhs)
+    : _root(),
+      _level(rhs._level)
 {
-    // empty
-}
-
-Trace::Trace(uint32_t level) :
-    _level(level),
-    _root()
-{
-    // empty
-}
-
-Trace::~Trace() = default;
-
-Trace &
-Trace::clear()
-{
-    _level = 0;
-    _root.clear();
-    return *this;
-}
-
-Trace &
-Trace::swap(Trace &other)
-{
-    std::swap(_level, other._level);
-    _root.swap(other._root);
-    return *this;
-}
-
-Trace &
-Trace::setLevel(uint32_t level)
-{
-    _level = std::min(level, 9u);
-    return *this;
+    if (!rhs.isEmpty()) {
+        _root = std::make_unique<TraceNode>(rhs.getRoot());
+    }
 }
 
 bool
@@ -53,12 +23,36 @@ Trace::trace(uint32_t level, const string &note, bool addTime)
     }
     if (addTime) {
         struct timeval tv;
-        gettimeofday(&tv, NULL);
-        _root.addChild(make_string("[%ld.%06ld] %s", tv.tv_sec, static_cast<long>(tv.tv_usec), note.c_str()));
+        gettimeofday(&tv, nullptr);
+        ensureRoot().addChild(make_string("[%ld.%06ld] %s", tv.tv_sec, static_cast<long>(tv.tv_usec), note.c_str()));
     } else {
-        _root.addChild(note);
+        ensureRoot().addChild(note);
     }
     return true;
 }
 
+string
+Trace::toString(size_t limit) const {
+    return _root ? _root->toString(limit) : "";
+}
+
+string
+Trace::encode() const {
+    return isEmpty() ? "" : getRoot().encode();
+}
+
+void
+Trace::clear() {
+    _level = 0;
+    _root.reset();
+}
+
+TraceNode &
+Trace::ensureRoot() {
+    if (!_root) {
+        _root = std::make_unique<TraceNode>();
+    }
+    return *_root;
+}
+
 } // namespace vespalib
diff --git a/vespalib/src/vespa/vespalib/trace/trace.h b/vespalib/src/vespa/vespalib/trace/trace.h
index d1ca5c5d7e7..2f70785d77d 100644
--- a/vespalib/src/vespa/vespalib/trace/trace.h
+++ b/vespalib/src/vespa/vespalib/trace/trace.h
@@ -18,31 +18,23 @@ namespace vespalib {
  * information will be traced.
  */
 class Trace {
-private:
-    uint32_t  _level;
-    TraceNode _root;
-
 public:
 
     /**
      * Create an empty Trace with level set to 0 (no tracing)
      */
-    Trace();
-    ~Trace();
-
-    /**
-     * Create an empty trace with given level.
-     *
-     * @param level Level to set.
-     */
-    explicit Trace(uint32_t level);
+    Trace() : Trace(0) {}
+    explicit Trace(uint32_t level) : _root(), _level(level) { }
+    Trace & operator = (Trace &&) = default;
+    Trace(Trace &&) = default;
+    Trace(const Trace &);
+    Trace & operator = (const Trace &) = delete;
+    ~Trace() = default;
 
     /**
      * Remove all trace information and set the trace level to 0.
-     *
-     * @return This, to allow chaining.
      */
-    Trace &clear();
+    void clear();
 
     /**
      * Swap the internals of this with another.
@@ -50,21 +42,16 @@ public:
      * @param other The trace to swap internals with.
      * @return This, to allow chaining.
      */
-    Trace &swap(Trace &other);
+    Trace &swap(Trace &other) {
+        std::swap(_level, other._level);
+        _root.swap(other._root);
+        return *this;
+    }
 
-    /**
-     * Set the trace level. 0 means no tracing, 9 means enable all tracing.
-     *
-     * @param level The level to set.
-     * @return This, to allow chaining.
-     */
-    Trace &setLevel(uint32_t level);
+    void setLevel(uint32_t level) {
+        _level = std::min(level, 9u);
+    }
 
-    /**
-     * Returns the trace level.
-     *
-     * @return The trace level.
-     */
     uint32_t getLevel() const { return _level; }
 
     /**
@@ -91,19 +78,29 @@ public:
      */
     bool trace(uint32_t level, const string &note, bool addTime = true);
 
-    /**
-     * Returns the root of the trace tree.
-     *
-     * @return The root.
-     */
-    TraceNode &getRoot() { return _root; }
+    void normalize() {
+        if (_root) {
+            _root->normalize();
+        }
+    }
 
-    /**
-     * Returns a const reference to the root of the trace tree.
-     *
-     * @return The root.
-     */
-    const TraceNode &getRoot() const { return _root; }
+    void setStrict(bool strict) {
+        ensureRoot().setStrict(strict);
+    }
+    void addChild(TraceNode && child) {
+        ensureRoot().addChild(std::move(child));
+    }
+    void addChild(Trace && child) {
+        if (!child.isEmpty()) {
+            addChild(std::move(*child._root));
+        }
+    }
+
+    bool isEmpty() const { return !_root || _root->isEmpty(); }
+
+    uint32_t getNumChildren() const { return _root ? _root->getNumChildren() : 0; }
+    const TraceNode & getChild(uint32_t child) const { return getRoot().getChild(child); }
+    string encode() const;
 
     /**
      * Returns a string representation of the contained trace tree. This is a
@@ -111,7 +108,16 @@ public:
      *
      * @return Readable trace string.
      */
-    string toString() const { return _root.toString(31337); }
+    string toString(size_t limit=31337) const;
+    size_t computeMemoryUsage() const {
+        return _root ? _root->computeMemoryUsage() : 0;
+    }
+private:
+    const TraceNode &getRoot() const { return *_root; }
+    TraceNode &ensureRoot();
+
+    std::unique_ptr<TraceNode> _root;
+    uint32_t  _level;
 };
 
 #define VESPALIB_TRACE2(ttrace, level, note, addTime) \
diff --git a/vespalib/src/vespa/vespalib/trace/tracenode.cpp b/vespalib/src/vespa/vespalib/trace/tracenode.cpp
index d34b45025d3..12dd51ac677 100644
--- a/vespalib/src/vespa/vespalib/trace/tracenode.cpp
+++ b/vespalib/src/vespa/vespalib/trace/tracenode.cpp
@@ -40,22 +40,22 @@ struct Cmp {
 } // namespace <unnamed>
 
 
-TraceNode::TraceNode() :
-    _parent(nullptr),
-    _strict(true),
-    _hasNote(false),
-    _note(""),
-    _children(),
-    _timestamp()
+TraceNode::TraceNode()
+    : _note(""),
+      _children(),
+      _parent(nullptr),
+      _timestamp(),
+      _strict(true),
+      _hasNote(false)
 { }
 
-TraceNode::TraceNode(const TraceNode &rhs) :
-    _parent(nullptr),
-    _strict(rhs._strict),
-    _hasNote(rhs._hasNote),
-    _note(rhs._note),
-    _children(),
-    _timestamp(rhs._timestamp)
+TraceNode::TraceNode(const TraceNode &rhs)
+    : _note(rhs._note),
+      _children(),
+      _parent(nullptr),
+      _timestamp(rhs._timestamp),
+      _strict(rhs._strict),
+      _hasNote(rhs._hasNote)
 {
     addChildren(rhs._children);
 }
@@ -65,22 +65,22 @@ TraceNode & TraceNode::operator =(const TraceNode &) = default;
 
 TraceNode::~TraceNode() = default;
 
-TraceNode::TraceNode(const string &note, system_time timestamp) :
-    _parent(nullptr),
-    _strict(true),
-    _hasNote(true),
-    _note(note),
-    _children(),
-    _timestamp(timestamp)
+TraceNode::TraceNode(const string &note, system_time timestamp)
+    : _note(note),
+      _children(),
+      _parent(nullptr),
+      _timestamp(timestamp),
+      _strict(true),
+      _hasNote(true)
 { }
 
-TraceNode::TraceNode(system_time timestamp) :
-    _parent(nullptr),
-    _strict(true),
-    _hasNote(false),
-    _note(""),
-    _children(),
-    _timestamp(timestamp)
+TraceNode::TraceNode(system_time timestamp)
+    : _note(""),
+      _children(),
+      _parent(nullptr),
+      _timestamp(timestamp),
+      _strict(true),
+      _hasNote(false)
 { }
 
 TraceNode &
@@ -342,4 +342,17 @@ TraceNode::accept(TraceVisitor & visitor) const
     return visitor;
 }
 
+size_t
+TraceNode::computeMemoryUsage() const
+{
+    if (isLeaf()) {
+        return getNote().size();
+    }
+    size_t childSum = 0;
+    for (const TraceNode & child : _children) {
+        childSum += child.computeMemoryUsage();
+    }
+    return childSum;
+}
+
 } // namespace vespalib
diff --git a/vespalib/src/vespa/vespalib/trace/tracenode.h b/vespalib/src/vespa/vespalib/trace/tracenode.h
index 63e7bcd6dc0..7a7cdb89c69 100644
--- a/vespalib/src/vespa/vespalib/trace/tracenode.h
+++ b/vespalib/src/vespa/vespalib/trace/tracenode.h
@@ -23,12 +23,12 @@ struct TraceVisitor;
  */
 class TraceNode {
 private:
-    TraceNode             *_parent;
-    bool                   _strict;
-    bool                   _hasNote;
     string                 _note;
     std::vector<TraceNode> _children;
+    TraceNode             *_parent;
     system_time            _timestamp;
+    bool                   _strict;
+    bool                   _hasNote;
 
 public:
     /**
@@ -253,6 +253,8 @@ public:
      */
     TraceVisitor & accept(TraceVisitor & visitor) const;
 
+    size_t computeMemoryUsage() const;
+
 };
 
 } // namespace vespalib