diff --git a/CMakeLists.txt b/CMakeLists.txt
index a8ad95fc8..3655c79c2 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -131,6 +131,9 @@ set(SOURCES
         db/write_batch_base.cc
         db/write_controller.cc
         db/write_thread.cc
+        memtable/hash_cuckoo_rep.cc
+        memtable/hash_linklist_rep.cc
+        memtable/hash_skiplist_rep.cc
         port/stack_trace.cc
         port/win/env_win.cc
         port/win/port_win.cc
@@ -185,9 +188,6 @@ set(SOURCES
         util/file_reader_writer.cc
         util/filter_policy.cc
         util/hash.cc
-        util/hash_cuckoo_rep.cc
-        util/hash_linklist_rep.cc
-        util/hash_skiplist_rep.cc
         util/histogram.cc
         util/instrumented_mutex.cc
         util/iostats_context.cc
diff --git a/db/column_family.cc b/db/column_family.cc
index 88bf0339b..f6233a729 100644
--- a/db/column_family.cc
+++ b/db/column_family.cc
@@ -27,9 +27,9 @@
 #include "db/version_set.h"
 #include "db/write_controller.h"
 #include "db/writebuffer.h"
+#include "memtable/hash_skiplist_rep.h"
 #include "util/autovector.h"
 #include "util/compression.h"
-#include "util/hash_skiplist_rep.h"
 #include "util/options_helper.h"
 #include "util/thread_status_util.h"
 #include "util/xfunc.h"
diff --git a/db/compaction_job_stats_test.cc b/db/compaction_job_stats_test.cc
index 1d69e61f0..d6a82e18d 100644
--- a/db/compaction_job_stats_test.cc
+++ b/db/compaction_job_stats_test.cc
@@ -27,6 +27,7 @@
 #include "db/job_context.h"
 #include "db/version_set.h"
 #include "db/write_batch_internal.h"
+#include "memtable/hash_linklist_rep.h"
 #include "port/stack_trace.h"
 #include "rocksdb/cache.h"
 #include "rocksdb/compaction_filter.h"
@@ -50,7 +51,6 @@
 #include "table/scoped_arena_iterator.h"
 #include "util/compression.h"
 #include "util/hash.h"
-#include "util/hash_linklist_rep.h"
 #include "util/logging.h"
 #include "util/mock_env.h"
 #include "util/mutexlock.h"
diff --git a/db/comparator_db_test.cc b/db/comparator_db_test.cc
index cb944a76a..530c91060 100644
--- a/db/comparator_db_test.cc
+++ b/db/comparator_db_test.cc
@@ -7,10 +7,11 @@
 #include <map>
 #include <string>
 
+#include "memtable/stl_wrappers.h"
 #include "rocksdb/db.h"
 #include "rocksdb/env.h"
 #include "util/hash.h"
-#include "util/stl_wrappers.h"
+#include "util/kv_map.h"
 #include "util/string_util.h"
 #include "util/testharness.h"
 #include "util/testutil.h"
diff --git a/db/db_impl.cc b/db/db_impl.cc
index fe10e2086..034b51495 100644
--- a/db/db_impl.cc
+++ b/db/db_impl.cc
@@ -50,6 +50,8 @@
 #include "db/write_batch_internal.h"
 #include "db/write_callback.h"
 #include "db/writebuffer.h"
+#include "memtable/hash_linklist_rep.h"
+#include "memtable/hash_skiplist_rep.h"
 #include "port/likely.h"
 #include "port/port.h"
 #include "rocksdb/cache.h"
@@ -77,8 +79,6 @@
 #include "util/db_info_dumper.h"
 #include "util/file_reader_writer.h"
 #include "util/file_util.h"
-#include "util/hash_linklist_rep.h"
-#include "util/hash_skiplist_rep.h"
 #include "util/iostats_context_imp.h"
 #include "util/log_buffer.h"
 #include "util/logging.h"
diff --git a/db/db_test.cc b/db/db_test.cc
index 8698251d2..690fdf812 100644
--- a/db/db_test.cc
+++ b/db/db_test.cc
@@ -30,6 +30,7 @@
 #include "db/job_context.h"
 #include "db/version_set.h"
 #include "db/write_batch_internal.h"
+#include "memtable/hash_linklist_rep.h"
 #include "port/stack_trace.h"
 #include "rocksdb/cache.h"
 #include "rocksdb/compaction_filter.h"
@@ -57,7 +58,6 @@
 #include "table/scoped_arena_iterator.h"
 #include "util/file_reader_writer.h"
 #include "util/hash.h"
-#include "util/hash_linklist_rep.h"
 #include "utilities/merge_operators.h"
 #include "util/logging.h"
 #include "util/compression.h"
diff --git a/db/db_test_util.h b/db/db_test_util.h
index 9f1b96a71..befd6cd8c 100644
--- a/db/db_test_util.h
+++ b/db/db_test_util.h
@@ -30,6 +30,7 @@
 #include "db/db_test_util.h"
 #include "db/dbformat.h"
 #include "db/filename.h"
+#include "memtable/hash_linklist_rep.h"
 #include "rocksdb/cache.h"
 #include "rocksdb/compaction_filter.h"
 #include "rocksdb/convenience.h"
@@ -45,7 +46,6 @@
 #include "table/plain_table_factory.h"
 #include "table/scoped_arena_iterator.h"
 #include "util/compression.h"
-#include "util/hash_linklist_rep.h"
 #include "util/mock_env.h"
 #include "util/mutexlock.h"
 
diff --git a/db/listener_test.cc b/db/listener_test.cc
index 0880a6597..08fe096dc 100644
--- a/db/listener_test.cc
+++ b/db/listener_test.cc
@@ -8,6 +8,7 @@
 #include "db/filename.h"
 #include "db/version_set.h"
 #include "db/write_batch_internal.h"
+#include "memtable/hash_linklist_rep.h"
 #include "rocksdb/cache.h"
 #include "rocksdb/compaction_filter.h"
 #include "rocksdb/db.h"
@@ -22,7 +23,6 @@
 #include "table/block_based_table_factory.h"
 #include "table/plain_table_factory.h"
 #include "util/hash.h"
-#include "util/hash_linklist_rep.h"
 #include "util/logging.h"
 #include "util/mutexlock.h"
 #include "util/rate_limiter.h"
diff --git a/util/hash_cuckoo_rep.cc b/memtable/hash_cuckoo_rep.cc
similarity index 99%
rename from util/hash_cuckoo_rep.cc
rename to memtable/hash_cuckoo_rep.cc
index 6e5057a73..447113ddf 100644
--- a/util/hash_cuckoo_rep.cc
+++ b/memtable/hash_cuckoo_rep.cc
@@ -5,8 +5,7 @@
 //
 
 #ifndef ROCKSDB_LITE
-
-#include "util/hash_cuckoo_rep.h"
+#include "memtable/hash_cuckoo_rep.h"
 
 #include <algorithm>
 #include <atomic>
@@ -18,9 +17,10 @@
 
 #include "db/memtable.h"
 #include "db/skiplist.h"
+#include "memtable/stl_wrappers.h"
+#include "port/port.h"
 #include "rocksdb/memtablerep.h"
 #include "util/murmurhash.h"
-#include "util/stl_wrappers.h"
 
 namespace rocksdb {
 namespace {
diff --git a/util/hash_cuckoo_rep.h b/memtable/hash_cuckoo_rep.h
similarity index 98%
rename from util/hash_cuckoo_rep.h
rename to memtable/hash_cuckoo_rep.h
index 9f374a978..6de4baa20 100644
--- a/util/hash_cuckoo_rep.h
+++ b/memtable/hash_cuckoo_rep.h
@@ -6,8 +6,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
 
-#ifndef ROCKSDB_LITE
 #pragma once
+#ifndef ROCKSDB_LITE
+#include "port/port.h"
 #include "rocksdb/slice_transform.h"
 #include "rocksdb/memtablerep.h"
 
diff --git a/util/hash_linklist_rep.cc b/memtable/hash_linklist_rep.cc
similarity index 99%
rename from util/hash_linklist_rep.cc
rename to memtable/hash_linklist_rep.cc
index 1e6eadfe6..2e761ce15 100644
--- a/util/hash_linklist_rep.cc
+++ b/memtable/hash_linklist_rep.cc
@@ -5,7 +5,7 @@
 //
 
 #ifndef ROCKSDB_LITE
-#include "util/hash_linklist_rep.h"
+#include "memtable/hash_linklist_rep.h"
 
 #include <algorithm>
 #include <atomic>
diff --git a/util/hash_linklist_rep.h b/memtable/hash_linklist_rep.h
similarity index 100%
rename from util/hash_linklist_rep.h
rename to memtable/hash_linklist_rep.h
index 629272394..1bab441ed 100644
--- a/util/hash_linklist_rep.h
+++ b/memtable/hash_linklist_rep.h
@@ -6,8 +6,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
 
-#ifndef ROCKSDB_LITE
 #pragma once
+#ifndef ROCKSDB_LITE
 #include "rocksdb/slice_transform.h"
 #include "rocksdb/memtablerep.h"
 
diff --git a/util/hash_skiplist_rep.cc b/memtable/hash_skiplist_rep.cc
similarity index 99%
rename from util/hash_skiplist_rep.cc
rename to memtable/hash_skiplist_rep.cc
index 142903d42..cbdd88993 100644
--- a/util/hash_skiplist_rep.cc
+++ b/memtable/hash_skiplist_rep.cc
@@ -5,7 +5,7 @@
 //
 
 #ifndef ROCKSDB_LITE
-#include "util/hash_skiplist_rep.h"
+#include "memtable/hash_skiplist_rep.h"
 
 #include <atomic>
 
diff --git a/util/hash_skiplist_rep.h b/memtable/hash_skiplist_rep.h
similarity index 100%
rename from util/hash_skiplist_rep.h
rename to memtable/hash_skiplist_rep.h
index 15d0fc77f..a6544ff04 100644
--- a/util/hash_skiplist_rep.h
+++ b/memtable/hash_skiplist_rep.h
@@ -6,8 +6,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
 
-#ifndef ROCKSDB_LITE
 #pragma once
+#ifndef ROCKSDB_LITE
 #include "rocksdb/slice_transform.h"
 #include "rocksdb/memtablerep.h"
 
diff --git a/util/stl_wrappers.h b/memtable/stl_wrappers.h
similarity index 73%
rename from util/stl_wrappers.h
rename to memtable/stl_wrappers.h
index 15b9bdf52..cef8301fa 100644
--- a/util/stl_wrappers.h
+++ b/memtable/stl_wrappers.h
@@ -30,17 +30,5 @@ struct Compare : private Base {
   }
 };
 
-struct LessOfComparator {
-  explicit LessOfComparator(const Comparator* c = BytewiseComparator())
-      : cmp(c) {}
-
-  bool operator()(const std::string& a, const std::string& b) const {
-    return cmp->Compare(Slice(a), Slice(b)) < 0;
-  }
-
-  const Comparator* cmp;
-};
-
-typedef std::map<std::string, std::string, LessOfComparator> KVMap;
 }
 }
diff --git a/src.mk b/src.mk
index c975b7e6b..7b3f15b19 100644
--- a/src.mk
+++ b/src.mk
@@ -46,6 +46,9 @@ LIB_SOURCES =                                                   \
   db/write_batch_base.cc                                        \
   db/write_controller.cc                                        \
   db/write_thread.cc                                            \
+  memtable/hash_cuckoo_rep.cc                                   \
+  memtable/hash_linklist_rep.cc                                 \
+  memtable/hash_skiplist_rep.cc                                 \
   port/stack_trace.cc                                           \
   port/port_posix.cc                                            \
   table/adaptive_table_factory.cc                               \
@@ -96,9 +99,6 @@ LIB_SOURCES =                                                   \
   util/file_reader_writer.cc                                    \
   util/filter_policy.cc                                         \
   util/hash.cc                                                  \
-  util/hash_cuckoo_rep.cc                                       \
-  util/hash_linklist_rep.cc                                     \
-  util/hash_skiplist_rep.cc                                     \
   util/histogram.cc                                             \
   util/instrumented_mutex.cc                                    \
   util/iostats_context.cc                                       \
diff --git a/table/meta_blocks.h b/table/meta_blocks.h
index 3dddc4427..085ae308e 100644
--- a/table/meta_blocks.h
+++ b/table/meta_blocks.h
@@ -11,12 +11,12 @@
 
 #include "db/builder.h"
 #include "db/table_properties_collector.h"
+#include "util/kv_map.h"
 #include "rocksdb/comparator.h"
 #include "rocksdb/options.h"
 #include "rocksdb/slice.h"
 #include "table/block_builder.h"
 #include "table/format.h"
-#include "util/stl_wrappers.h"
 
 namespace rocksdb {
 
diff --git a/table/mock_table.h b/table/mock_table.h
index 8f6e53321..c13636af1 100644
--- a/table/mock_table.h
+++ b/table/mock_table.h
@@ -14,6 +14,7 @@
 #include <string>
 #include <utility>
 
+#include "util/kv_map.h"
 #include "port/port.h"
 #include "rocksdb/comparator.h"
 #include "rocksdb/table.h"
@@ -21,7 +22,6 @@
 #include "table/table_builder.h"
 #include "table/table_reader.h"
 #include "util/mutexlock.h"
-#include "util/stl_wrappers.h"
 #include "util/testharness.h"
 #include "util/testutil.h"
 
diff --git a/table/table_test.cc b/table/table_test.cc
index 7d93d067e..58607bbb2 100644
--- a/table/table_test.cc
+++ b/table/table_test.cc
@@ -21,6 +21,7 @@
 #include "db/memtable.h"
 #include "db/write_batch_internal.h"
 #include "db/writebuffer.h"
+#include "memtable/stl_wrappers.h"
 #include "rocksdb/cache.h"
 #include "rocksdb/db.h"
 #include "rocksdb/env.h"
@@ -43,7 +44,6 @@
 #include "util/compression.h"
 #include "util/random.h"
 #include "util/statistics.h"
-#include "util/stl_wrappers.h"
 #include "util/string_util.h"
 #include "util/testharness.h"
 #include "util/testutil.h"
diff --git a/util/kv_map.h b/util/kv_map.h
new file mode 100644
index 000000000..486db1918
--- /dev/null
+++ b/util/kv_map.h
@@ -0,0 +1,31 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+#pragma once
+
+#include <map>
+#include <string>
+
+#include "rocksdb/comparator.h"
+#include "rocksdb/slice.h"
+#include "util/coding.h"
+#include "util/murmurhash.h"
+
+namespace rocksdb {
+namespace stl_wrappers {
+
+struct LessOfComparator {
+  explicit LessOfComparator(const Comparator* c = BytewiseComparator())
+      : cmp(c) {}
+
+  bool operator()(const std::string& a, const std::string& b) const {
+    return cmp->Compare(Slice(a), Slice(b)) < 0;
+  }
+
+  const Comparator* cmp;
+};
+
+typedef std::map<std::string, std::string, LessOfComparator> KVMap;
+}
+}
diff --git a/util/vectorrep.cc b/util/vectorrep.cc
index 017f89f7c..324439a1d 100644
--- a/util/vectorrep.cc
+++ b/util/vectorrep.cc
@@ -14,9 +14,9 @@
 
 #include "util/arena.h"
 #include "db/memtable.h"
+#include "memtable/stl_wrappers.h"
 #include "port/port.h"
 #include "util/mutexlock.h"
-#include "util/stl_wrappers.h"
 
 namespace rocksdb {
 namespace {