diff --git a/mace/benchmark/stat_summarizer.cc b/mace/benchmark/stat_summarizer.cc
deleted file mode 100644
index 291fd5ded7cf71097e23c7ea7a04a951a8c7dd95..0000000000000000000000000000000000000000
--- a/mace/benchmark/stat_summarizer.cc
+++ /dev/null
@@ -1,406 +0,0 @@
-// Copyright 2018 Xiaomi, Inc.  All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#include "mace/benchmark/stat_summarizer.h"
-
-#include <iomanip>
-#include <iostream>
-#include <queue>
-#include <utility>
-
-#include "mace/public/mace.h"
-#include "mace/utils/logging.h"
-#include "mace/core/types.h"
-#include "mace/kernels/conv_pool_2d_util.h"
-
-namespace mace {
-namespace benchmark {
-
-StatSummarizer::StatSummarizer(const StatSummarizerOptions &options)
-    : options_(options) {}
-
-StatSummarizer::~StatSummarizer() {}
-
-void StatSummarizer::Reset() {
-  run_total_us_.Reset();
-  memory_.Reset();
-  details_.clear();
-}
-
-void StatSummarizer::ProcessMetadata(const RunMetadata &run_metadata) {
-  int64_t curr_total_us = 0;
-  int64_t mem_total = 0;
-
-  if (run_metadata.op_stats.empty()) {
-    std::cerr << "Runtime op stats should not be empty" << std::endl;
-    abort();
-  }
-  int64_t first_node_start_us = run_metadata.op_stats[0].stats.start_micros;
-
-  int node_num = 0;
-  for (const auto &ops : run_metadata.op_stats) {
-    std::string name = ops.operator_name;
-    std::string op_type = ops.type;
-
-    ++node_num;
-    const int64_t curr_time = ops.stats.end_micros - ops.stats.start_micros;
-    curr_total_us += curr_time;
-    auto result = details_.emplace(name, Detail());
-    Detail *detail = &(result.first->second);
-
-    detail->start_us.UpdateStat(ops.stats.start_micros - first_node_start_us);
-    detail->rel_end_us.UpdateStat(curr_time);
-
-    // If this is the first pass, initialize some values.
-    if (result.second) {
-      detail->name = name;
-      detail->type = op_type;
-      detail->output_shape = ops.output_shape;
-      detail->args = ops.args;
-
-      detail->run_order = node_num;
-
-      detail->times_called = 0;
-    }
-
-    ++detail->times_called;
-  }
-
-  run_total_us_.UpdateStat(curr_total_us);
-  memory_.UpdateStat(mem_total);
-}
-
-std::string StatSummarizer::ShortSummary() const {
-  std::stringstream stream;
-  stream << "Timings (microseconds): ";
-  run_total_us_.OutputToStream(&stream);
-  stream << std::endl;
-
-  stream << "Memory (bytes): ";
-  memory_.OutputToStream(&stream);
-  stream << std::endl;
-
-  stream << details_.size() << " nodes observed" << std::endl;
-  return stream.str();
-}
-
-std::ostream &InitField(std::ostream &stream, int width) {
-  stream << std::right << std::setw(width) << std::fixed
-         << std::setprecision(3);
-  return stream;
-}
-
-std::string StatSummarizer::HeaderString(const std::string &title) const {
-  std::stringstream stream;
-
-  stream << "============================== " << title
-         << " ==============================" << std::endl;
-
-  InitField(stream, 24) << "[node type]";
-  InitField(stream, 9) << "[start]";
-  InitField(stream, 9) << "[first]";
-  InitField(stream, 9) << "[avg ms]";
-  InitField(stream, 9) << "[%]";
-  InitField(stream, 9) << "[cdf%]";
-  InitField(stream, 10) << "[mem KB]";
-  InitField(stream, 10) << "[Name]";
-  InitField(stream, 8) << "[stride]";
-  InitField(stream, 10) << "[padding]";
-  InitField(stream, 10) << "[dilation]";
-  InitField(stream, 15) << "[kernel]";
-  stream << std::right << std::setw(45) << "[output shape]";
-
-  return stream.str();
-}
-
-std::string PaddingTypeToString(int padding_type) {
-  std::stringstream stream;
-  Padding type = static_cast<Padding>(padding_type);
-  switch (type) {
-    case VALID: stream << "VALID"; break;
-    case SAME: stream << "SAME"; break;
-    case FULL: stream << "FULL"; break;
-    default: stream << padding_type; break;
-  }
-
-  return stream.str();
-}
-
-std::string ShapeToString(const std::vector<OutputShape> &output_shape) {
-  if (output_shape.empty()) {
-    return "";
-  }
-
-  std::stringstream stream;
-  stream << "[";
-  for (int i = 0; i < output_shape.size(); ++i) {
-    const std::vector<index_t> &dims = output_shape[i].dims();
-    for (int j = 0; j < dims.size(); ++j) {
-      stream << dims[j];
-      if (j != dims.size() - 1) {
-        stream << ",";
-      }
-    }
-    if (i != output_shape.size() - 1) {
-      stream << ":";
-    }
-  }
-  stream << "]";
-
-  return stream.str();
-}
-
-template <typename T>
-std::string VectorToString(const std::vector<T> &vec) {
-  if (vec.empty()) {
-    return "";
-  }
-
-  std::stringstream stream;
-  stream << "[";
-  for (int i = 0; i < vec.size(); ++i) {
-    stream << vec[i];
-    if (i != vec.size() - 1) {
-      stream << ",";
-    }
-  }
-  stream << "]";
-
-  return stream.str();
-}
-
-std::string StatSummarizer::ColumnString(const StatSummarizer::Detail &detail,
-                                         const int64_t cumulative_stat_on_node,
-                                         const Stat<int64_t> &stat) const {
-  const double start_ms = detail.start_us.avg() / 1000.0;
-  const double first_time_ms = detail.rel_end_us.first() / 1000.0;
-  const double avg_time_ms = detail.rel_end_us.avg() / 1000.0;
-  const double percentage = detail.rel_end_us.sum() * 100.0 / stat.sum();
-  const double cdf_percentage = (cumulative_stat_on_node * 100.0f) / stat.sum();
-
-  std::stringstream stream;
-  InitField(stream, 24) << detail.type;
-  InitField(stream, 9) << start_ms;
-  InitField(stream, 9) << first_time_ms;
-  InitField(stream, 9) << avg_time_ms;
-  InitField(stream, 8) << percentage << "%";
-  InitField(stream, 8) << cdf_percentage << "%";
-  InitField(stream, 10) << detail.mem_used.newest() / 1000.0;
-  InitField(stream, 10) << detail.name;
-  InitField(stream, 8) << VectorToString<int>(detail.args.strides);
-  if (detail.args.padding_type != -1) {
-    InitField(stream, 10) << PaddingTypeToString(detail.args.padding_type);
-  } else {
-    InitField(stream, 10) << VectorToString<int>(detail.args.paddings);
-  }
-  InitField(stream, 10) << VectorToString<int>(detail.args.dilations);
-  InitField(stream, 15) << VectorToString<index_t>(detail.args.kernels);
-  stream << std::right << std::setw(45) << ShapeToString(detail.output_shape);
-
-  return stream.str();
-}
-
-void StatSummarizer::OrderNodesByMetric(
-    SortingMetric metric, std::vector<const Detail *> *details) const {
-  std::priority_queue<std::pair<std::string, const Detail *>> sorted_list;
-  const int num_nodes = details_.size();
-
-  for (const auto &det : details_) {
-    const Detail *detail = &(det.second);
-
-    std::stringstream stream;
-    stream << std::setw(20) << std::right << std::setprecision(10)
-           << std::fixed;
-
-    switch (metric) {
-      case BY_NAME:
-        stream << detail->name;
-        break;
-      case BY_RUN_ORDER:
-        stream << num_nodes - detail->run_order;
-        break;
-      case BY_TIME:
-        stream << detail->rel_end_us.avg();
-        break;
-      case BY_MEMORY:
-        stream << detail->mem_used.avg();
-        break;
-      case BY_TYPE:
-        stream << detail->type;
-        break;
-      default:
-        stream << "";
-        break;
-    }
-
-    sorted_list.emplace(stream.str(), detail);
-  }
-
-  while (!sorted_list.empty()) {
-    auto entry = sorted_list.top();
-    sorted_list.pop();
-    details->push_back(entry.second);
-  }
-}
-
-void StatSummarizer::ComputeStatsByType(
-    std::map<std::string, int64_t> *node_type_map_count,
-    std::map<std::string, int64_t> *node_type_map_time,
-    std::map<std::string, int64_t> *node_type_map_memory,
-    std::map<std::string, int64_t> *node_type_map_times_called,
-    int64_t *accumulated_us) const {
-  int64_t run_count = run_total_us_.count();
-
-  for (const auto &det : details_) {
-    const std::string node_name = det.first;
-    const Detail &detail = det.second;
-
-    int64_t curr_time_val =
-        static_cast<int64_t>(detail.rel_end_us.sum() / run_count);
-    *accumulated_us += curr_time_val;
-
-    int64_t curr_memory_val = detail.mem_used.newest();
-
-    const std::string &node_type = detail.type;
-
-    (*node_type_map_count)[node_type] += 1;
-    (*node_type_map_time)[node_type] += curr_time_val;
-    (*node_type_map_memory)[node_type] += curr_memory_val;
-    (*node_type_map_times_called)[node_type] += detail.times_called / run_count;
-  }
-}
-
-std::string StatSummarizer::GetStatsByNodeType() const {
-  std::stringstream stream;
-
-  stream << "============================== Summary by node type "
-            "=============================="
-         << std::endl;
-
-  LOG(INFO) << "Number of nodes executed: " << details_.size() << std::endl;
-
-  std::map<std::string, int64_t> node_type_map_count;
-  std::map<std::string, int64_t> node_type_map_time;
-  std::map<std::string, int64_t> node_type_map_memory;
-  std::map<std::string, int64_t> node_type_map_times_called;
-  int64_t accumulated_us = 0;
-
-  ComputeStatsByType(&node_type_map_count, &node_type_map_time,
-                     &node_type_map_memory, &node_type_map_times_called,
-                     &accumulated_us);
-
-  // Sort them.
-  std::priority_queue<std::pair<int64_t, std::pair<std::string, int64_t>>>
-      timings;
-  for (const auto &node_type : node_type_map_time) {
-    const int64_t mem_used = node_type_map_memory[node_type.first];
-    timings.emplace(node_type.second,
-                    std::pair<std::string, int64_t>(node_type.first, mem_used));
-  }
-
-  InitField(stream, 24) << "[Node type]";
-  InitField(stream, 9) << "[count]";
-  InitField(stream, 10) << "[avg ms]";
-  InitField(stream, 11) << "[avg %]";
-  InitField(stream, 11) << "[cdf %]";
-  InitField(stream, 10) << "[mem KB]";
-  InitField(stream, 10) << "[times called]";
-  stream << std::endl;
-
-  float cdf = 0.0f;
-  while (!timings.empty()) {
-    auto entry = timings.top();
-    timings.pop();
-
-    const std::string node_type = entry.second.first;
-    const float memory = entry.second.second / 1000.0f;
-
-    const int64_t node_type_total_us = entry.first;
-    const float time_per_run_ms = node_type_total_us / 1000.0f;
-
-    const float percentage =
-        ((entry.first / static_cast<float>(accumulated_us)) * 100.0f);
-    cdf += percentage;
-
-    InitField(stream, 24) << node_type;
-    InitField(stream, 9) << node_type_map_count[node_type];
-    InitField(stream, 10) << time_per_run_ms;
-    InitField(stream, 10) << percentage << "%";
-    InitField(stream, 10) << cdf << "%";
-    InitField(stream, 10) << memory;
-    InitField(stream, 9) << node_type_map_times_called[node_type];
-    stream << std::endl;
-  }
-  stream << std::endl;
-  return stream.str();
-}
-
-std::string StatSummarizer::GetStatsByMetric(const std::string &title,
-                                             SortingMetric sorting_metric,
-                                             int num_stats) const {
-  std::vector<const Detail *> details;
-  OrderNodesByMetric(sorting_metric, &details);
-
-  double cumulative_stat_on_node = 0;
-
-  std::stringstream stream;
-  stream << HeaderString(title) << std::endl;
-  int stat_num = 0;
-  for (auto detail : details) {
-    ++stat_num;
-    if (num_stats > 0 && stat_num > num_stats) {
-      break;
-    }
-
-    cumulative_stat_on_node += detail->rel_end_us.sum();
-    stream << ColumnString(*detail, cumulative_stat_on_node, run_total_us_)
-           << std::endl;
-  }
-  stream << std::endl;
-  return stream.str();
-}
-
-std::string StatSummarizer::GetOutputString() const {
-  std::stringstream stream;
-  if (options_.show_run_order) {
-    stream << GetStatsByMetric("Run Order", BY_RUN_ORDER,
-                               options_.run_order_limit);
-  }
-  if (options_.show_time) {
-    stream << GetStatsByMetric("Top by Computation Time", BY_TIME,
-                               options_.time_limit);
-  }
-  if (options_.show_memory) {
-    stream << GetStatsByMetric("Top by Memory Use", BY_MEMORY,
-                               options_.memory_limit);
-  }
-  if (options_.show_type) {
-    stream << GetStatsByNodeType();
-  }
-  if (options_.show_summary) {
-    stream << ShortSummary() << std::endl;
-  }
-  return stream.str();
-}
-
-void StatSummarizer::PrintOperatorStats() const {
-  std::string output = GetOutputString();
-  std::istringstream iss(output);
-  for (std::string line; std::getline(iss, line);) {
-    LOG(INFO) << line;
-  }
-}
-
-}  // namespace benchmark
-}  // namespace mace
diff --git a/mace/benchmark/stat_summarizer.h b/mace/benchmark/stat_summarizer.h
deleted file mode 100644
index e457dfc39ecb25a7bc038e3bc7d5ba0b2409866c..0000000000000000000000000000000000000000
--- a/mace/benchmark/stat_summarizer.h
+++ /dev/null
@@ -1,216 +0,0 @@
-// Copyright 2018 Xiaomi, Inc.  All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#ifndef MACE_BENCHMARK_STAT_SUMMARIZER_H_
-#define MACE_BENCHMARK_STAT_SUMMARIZER_H_
-
-#include <stdlib.h>
-#include <algorithm>
-#include <cmath>
-#include <limits>
-#include <map>
-#include <sstream>
-#include <string>
-#include <vector>
-
-#include "mace/public/mace_types.h"
-
-namespace mace {
-
-class RunMetadata;
-
-namespace benchmark {
-
-template <typename ValueType, typename HighPrecisionValueType = double>
-class Stat {
- public:
-  void UpdateStat(ValueType v) {
-    if (count_ == 0) {
-      first_ = v;
-    }
-
-    newest_ = v;
-    max_ = std::max(v, max_);
-    min_ = std::min(v, min_);
-    ++count_;
-    sum_ += v;
-    squared_sum_ += static_cast<HighPrecisionValueType>(v) * v;
-  }
-
-  void Reset() { new (this) Stat<ValueType, HighPrecisionValueType>(); }
-
-  bool empty() const { return count_ == 0; }
-
-  ValueType first() const { return first_; }
-
-  ValueType newest() const { return newest_; }
-
-  ValueType max() const { return max_; }
-
-  ValueType min() const { return min_; }
-
-  int64_t count() const { return count_; }
-
-  ValueType sum() const { return sum_; }
-
-  HighPrecisionValueType squared_sum() const { return squared_sum_; }
-
-  bool all_same() const { return (count_ == 0 || min_ == max_); }
-
-  HighPrecisionValueType avg() const {
-    return empty() ? std::numeric_limits<ValueType>::quiet_NaN()
-                   : static_cast<HighPrecisionValueType>(sum_) / count_;
-  }
-
-  ValueType std_deviation() const {
-    return all_same() ? 0 : std::sqrt(squared_sum_ / count_ - avg() * avg());
-  }
-
-  void OutputToStream(std::ostream *stream) const {
-    if (empty()) {
-      *stream << "count=0";
-    } else if (all_same()) {
-      *stream << "count=" << count_ << " curr=" << newest_;
-      if (count_ > 1) *stream << "(all same)";
-    } else {
-      *stream << "count=" << count_ << " first=" << first_
-              << " curr=" << newest_ << " min=" << min_ << " max=" << max_
-              << " avg=" << avg() << " std=" << std_deviation();
-    }
-  }
-
-  friend std::ostream &operator<<(std::ostream &stream,
-                                  const Stat<ValueType> &stat) {
-    stat.OutputToStream(&stream);
-    return stream;
-  }
-
- private:
-  ValueType first_ = 0;
-  ValueType newest_ = 0;
-  ValueType max_ = std::numeric_limits<ValueType>::min();
-  ValueType min_ = std::numeric_limits<ValueType>::max();
-  int64_t count_ = 0;
-  ValueType sum_ = 0;
-  HighPrecisionValueType squared_sum_ = 0;
-};
-
-// Used to control the output of the statistics summarizer;
-class StatSummarizerOptions {
- public:
-  StatSummarizerOptions()
-      : show_run_order(true),
-        run_order_limit(0),
-        show_time(true),
-        time_limit(10),
-        show_memory(true),
-        memory_limit(10),
-        show_type(true),
-        show_summary(true) {}
-
-  bool show_run_order;
-  int run_order_limit;
-  bool show_time;
-  int time_limit;
-  bool show_memory;
-  int memory_limit;
-  bool show_type;
-  bool show_summary;
-};
-
-// A StatSummarizer assists in performance analysis of Graph executions.
-//
-// It summarizes time spent executing (on GPU/CPU), memory used etc. across
-// multiple executions of a single Graph from the StepStats collected during
-// graph execution.
-//
-// See tensorflow/tools/benchmark/benchmark_model.cc for an example usage.
-class StatSummarizer {
- public:
-  enum SortingMetric {
-    BY_NAME,
-    BY_RUN_ORDER,
-    BY_TIME,
-    BY_MEMORY,
-    BY_TYPE,
-  };
-
-  explicit StatSummarizer(const StatSummarizerOptions &options);
-
-  ~StatSummarizer();
-
-  // Adds another run's StepStats output to the aggregate counts.
-  void ProcessMetadata(const RunMetadata &run_metadata);
-
-  // Returns a string detailing the accumulated runtime stats in a tab-separated
-  // format which can be pasted into a spreadsheet for further analysis.
-  std::string GetOutputString() const;
-
-  std::string ShortSummary() const;
-
-  // Prints the string returned by GetOutputString().
-  void PrintOperatorStats() const;
-
-  void ComputeStatsByType(
-      std::map<std::string, int64_t> *node_type_map_count,
-      std::map<std::string, int64_t> *node_type_map_time,
-      std::map<std::string, int64_t> *node_type_map_memory,
-      std::map<std::string, int64_t> *node_type_map_times_called,
-      int64_t *accumulated_us) const;
-
-  std::string GetStatsByNodeType() const;
-
-  std::string GetStatsByMetric(const std::string &title,
-                               SortingMetric sorting_metric,
-                               int num_stats) const;
-
-  void Reset();
-
-  // Returns number of runs.
-  int num_runs() const { return run_total_us_.count(); }
-
-  // Returns stats of total microseconds spent by all nodes in each run.
-  const Stat<int64_t> &run_total_us() const { return run_total_us_; }
-
- private:
-  struct Detail {
-    std::string name;
-    std::string type;
-    std::vector<mace::OutputShape> output_shape;
-    ConvPoolArgs args;
-    int64_t run_order;
-    Stat<int64_t> start_us;
-    Stat<int64_t> rel_end_us;
-    Stat<int64_t> mem_used;
-    int64_t times_called;
-  };
-
-  void OrderNodesByMetric(SortingMetric sorting_metric,
-                          std::vector<const Detail *> *details) const;
-
-  std::string HeaderString(const std::string &title) const;
-  std::string ColumnString(const Detail &detail,
-                           const int64_t cumulative_stat_on_node,
-                           const Stat<int64_t> &stat) const;
-  Stat<int64_t> run_total_us_;
-  Stat<int64_t> memory_;
-
-  std::map<std::string, Detail> details_;
-  StatSummarizerOptions options_;
-};
-
-}  // namespace benchmark
-}  // namespace mace
-
-#endif  // MACE_BENCHMARK_STAT_SUMMARIZER_H_
diff --git a/mace/utils/string_util.cc b/mace/utils/string_util.cc
index 31def7f15738866e588c520394f70f9a68c43e42..e41ba52220f486c0e4ba07814dcdc875994b57f4 100644
--- a/mace/utils/string_util.cc
+++ b/mace/utils/string_util.cc
@@ -75,8 +75,9 @@ std::string StringFormatter::Table(
       FormatRow(stream, max_column_len[h_idx]) << data[data_idx][h_idx];
       stream << " |";
     }
-    stream << std::endl << dash_line << std::endl;
+    stream << std::endl;
   }
+  stream << dash_line << std::endl;
   return stream.str();
 }