1 files changed, 38 insertions, 0 deletions
diff --git a/src/kv/KeyValueHistogram.h b/src/kv/KeyValueHistogram.h
new file mode 100644
index 000000000..2da44bd4e
--- /dev/null
+++ b/src/kv/KeyValueHistogram.h
@@ -0,0 +1,38 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+#ifndef KeyValueHistogram_H
+#define KeyValueHistogram_H
+
+#include <map>
+#include <string>
+#include "common/Formatter.h"
+
+/**
+ *
+ * Key Value DB Histogram generator
+ *
+ */
+struct KeyValueHistogram {
+  struct value_dist {
+    uint64_t count;
+    uint32_t max_len;
+  };
+
+  struct key_dist {
+    uint64_t count;
+    uint32_t max_len;
+    std::map<int, struct value_dist> val_map; ///< slab id to count, max length of value and key
+  };
+
+  std::map<std::string, std::map<int, struct key_dist> > key_hist;
+  std::map<int, uint64_t> value_hist;
+  int get_key_slab(size_t sz);
+  std::string get_key_slab_to_range(int slab);
+  int get_value_slab(size_t sz);
+  std::string get_value_slab_to_range(int slab);
+  void update_hist_entry(std::map<std::string, std::map<int, struct key_dist> >& key_hist,
+    const std::string& prefix, size_t key_size, size_t value_size);
+  void dump(ceph::Formatter* f);
+};
+
+#endif