Move `AddressSpace` from searchlib to vespalib

3 files changed, 62 insertions, 0 deletions

diff --git a/vespalib/src/vespa/vespalib/util/CMakeLists.txt b/vespalib/src/vespa/vespalib/util/CMakeLists.txt
index f8e06751c2a..00e232b77d4 100644
--- a/vespalib/src/vespa/vespalib/util/CMakeLists.txt
+++ b/vespalib/src/vespa/vespalib/util/CMakeLists.txt
@@ -2,6 +2,7 @@
 vespa_add_library(vespalib_vespalib_util OBJECT
     SOURCES
     active.cpp
+    address_space.cpp
     alloc.cpp
     approx.cpp
     array.cpp
diff --git a/vespalib/src/vespa/vespalib/util/address_space.cpp b/vespalib/src/vespa/vespalib/util/address_space.cpp
new file mode 100644
index 00000000000..058c00e835e
--- /dev/null
+++ b/vespalib/src/vespa/vespalib/util/address_space.cpp
@@ -0,0 +1,23 @@
+// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "address_space.h"
+#include <ostream>
+#include <cassert>
+
+namespace vespalib {
+
+AddressSpace::AddressSpace(size_t used_, size_t dead_, size_t limit_)
+    : _used(used_),
+      _dead(dead_),
+      _limit(limit_)
+{
+    assert(_used >= _dead);
+}
+
+std::ostream &operator << (std::ostream &out, const AddressSpace &rhs)
+{
+    return out << "used=" << rhs.used() << ", dead=" << rhs.dead() << ", limit=" << rhs.limit();
+}
+
+} // namespace vespalib
+
diff --git a/vespalib/src/vespa/vespalib/util/address_space.h b/vespalib/src/vespa/vespalib/util/address_space.h
new file mode 100644
index 00000000000..d88a5e06d80
--- /dev/null
+++ b/vespalib/src/vespa/vespalib/util/address_space.h
@@ -0,0 +1,38 @@
+// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#pragma once
+
+#include <iosfwd>
+
+namespace vespalib {
+
+/**
+ * Represents an address space with number of bytes/entries used
+ * and the limit number of bytes/entries this address space can represent.
+ */
+class AddressSpace
+{
+private:
+    size_t _used;
+    size_t _dead;
+    size_t _limit;
+
+public:
+    AddressSpace(size_t used_, size_t dead_, size_t limit_);
+    size_t used() const { return _used; }
+    size_t dead() const { return _dead; }
+    size_t limit() const  { return _limit; }
+    double usage() const {
+        if (_limit > 0) {
+            return (double)(_used - _dead) / (double)_limit;
+        }
+        return 0;
+    }
+    bool operator==(const AddressSpace &rhs) const {
+        return _used == rhs._used && _dead == rhs._dead && _limit == rhs._limit;
+    }
+};
+
+std::ostream &operator << (std::ostream &out, const AddressSpace &rhs);
+
+} // namespace search