space usage

Author: Gillgamesh

include/sketch/sketch_columns.h

@@ -48,6 +48,7 @@ class FixedSizeSketchColumn {
   void atomic_update(const vec_t update);
   void merge(FixedSizeSketchColumn const& other);
   uint8_t get_depth() const;
+  size_t space_usage_bytes() const;
   void serialize(std::ostream &binary_out) const;
 
   static uint8_t suggest_capacity(size_t num_indices) { 
@@ -131,6 +132,7 @@ FRIEND_TEST(SketchColumnTestSuite, TestUpdateReallocation);
   void atomic_apply_entry_delta(const ColumnEntryDelta &delta);
   void merge(ResizeableSketchColumn const& other);
   uint8_t get_depth() const;
+  size_t space_usage_bytes() const;
 
   [[deprecated]]
   void zero_contents() {
@@ -214,6 +216,7 @@ class ResizeableAlignedSketchColumn {
   }
   void merge(ResizeableAlignedSketchColumn const& other);
   uint8_t get_depth() const;
+  size_t space_usage_bytes() const;
 
   [[deprecated]]
   void zero_contents() {

include/sketch/sketch_concept.h

@@ -56,6 +56,7 @@ concept SketchColumnConcept = requires(T t, T other) {
   { t.prefetch() } -> std::same_as<void>; 
 
   { t.is_initialized() } -> std::same_as<bool>;
+  { t.space_usage_bytes() } -> std::same_as<size_t>;
 
   { t.clear()} -> std::same_as<void>;
   { t.zero_contents()} -> std::same_as<void>;

src/sketch_columns.cpp

@@ -69,6 +69,9 @@ uint8_t FixedSizeSketchColumn::get_depth() const {
   }
   return 0;
 }
+size_t FixedSizeSketchColumn::space_usage_bytes() const {
+  return sizeof(FixedSizeSketchColumn) + (capacity * sizeof(Bucket));
+}
 
 // TODO - implement actual deserialization
 void FixedSizeSketchColumn::serialize(std::ostream &binary_out) const {
@@ -400,6 +403,9 @@ uint8_t ResizeableSketchColumn::get_depth() const {
   }
   return 0;
 }
+size_t ResizeableSketchColumn::space_usage_bytes() const {
+  return sizeof(ResizeableSketchColumn) + (this->capacity * sizeof(Bucket));
+}
 
 
 
@@ -511,6 +517,9 @@ uint8_t ResizeableAlignedSketchColumn::get_depth() const {
   }
   return 0;
 }
+size_t ResizeableAlignedSketchColumn::space_usage_bytes() const{
+  return sizeof(ResizeableAlignedSketchColumn) + (this->capacity * sizeof(Bucket));
+}
 
 
 static_assert(SketchColumnConcept<FixedSizeSketchColumn, vec_t>,