Add methods to print memory usage.

3 files changed, 34 insertions, 4 deletions

diff --git a/vespalib/src/vespa/vespalib/util/CMakeLists.txt b/vespalib/src/vespa/vespalib/util/CMakeLists.txt
index d934a7b38ca..9d250d31563 100644
--- a/vespalib/src/vespa/vespalib/util/CMakeLists.txt
+++ b/vespalib/src/vespa/vespalib/util/CMakeLists.txt
@@ -31,6 +31,7 @@ vespa_add_library(vespalib_vespalib_util OBJECT
     left_right_heap.cpp
     lz4compressor.cpp
     md5.c
+    memoryusage.cpp
     mmap_file_allocator.cpp
     mmap_file_allocator_factory.cpp
     printable.cpp
diff --git a/vespalib/src/vespa/vespalib/util/memoryusage.cpp b/vespalib/src/vespa/vespalib/util/memoryusage.cpp
new file mode 100644
index 00000000000..6d6f93c3be0
--- /dev/null
+++ b/vespalib/src/vespa/vespalib/util/memoryusage.cpp
@@ -0,0 +1,24 @@
+// Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "memoryusage.h"
+#include <vespa/vespalib/stllike/asciistream.h>
+
+namespace vespalib {
+
+string
+MemoryUsage::toString() const {
+    vespalib::asciistream os;
+    os << *this;
+    return os.str();
+}
+
+asciistream &
+operator << (asciistream & os, const MemoryUsage & usage) {
+    os << "allocated: " << usage.allocatedBytes();
+    os << ", used: " << usage.usedBytes();
+    os << ", dead: " << usage.deadBytes();
+    os << ", onhold: " << usage.allocatedBytesOnHold();
+    return os;
+}
+
+} // namespace vespalib
diff --git a/vespalib/src/vespa/vespalib/util/memoryusage.h b/vespalib/src/vespa/vespalib/util/memoryusage.h
index 0ab339d1262..cc245ee69e9 100644
--- a/vespalib/src/vespa/vespalib/util/memoryusage.h
+++ b/vespalib/src/vespa/vespalib/util/memoryusage.h
@@ -1,8 +1,8 @@
-// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+// Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 
 #pragma once
 
-#include <cstddef>
+#include <vespa/vespalib/stllike/string.h>
 
 namespace vespalib {
 
@@ -14,14 +14,14 @@ private:
     size_t _allocatedBytesOnHold;
 
 public:
-    MemoryUsage()
+    MemoryUsage() noexcept
         : _allocatedBytes(0),
           _usedBytes(0),
           _deadBytes(0),
           _allocatedBytesOnHold(0)
     { }
 
-    MemoryUsage(size_t allocated, size_t used, size_t dead, size_t onHold)
+    MemoryUsage(size_t allocated, size_t used, size_t dead, size_t onHold) noexcept
         : _allocatedBytes(allocated),
           _usedBytes(used),
           _deadBytes(dead),
@@ -56,6 +56,11 @@ public:
         _deadBytes += rhs._deadBytes;
         _allocatedBytesOnHold += rhs._allocatedBytesOnHold;
     }
+    string toString() const;
 };
 
+class asciistream;
+
+asciistream & operator << (asciistream & os, const MemoryUsage & usage);
+
 } // namespace vespalib