text: //  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
  //  This source code is licensed under both the GPLv2 (found in the
  //  COPYING file in the root directory) and Apache 2.0 License
  //  (found in the LICENSE.Apache file in the root directory).
  //
  
  #include <sstream>
  #include "monitoring/perf_context_imp.h"
  
  namespace ROCKSDB_NAMESPACE {
  
  #if defined(NPERF_CONTEXT)
  // Should not be used because the counters are not thread-safe.
  // Put here just to make get_perf_context() simple without ifdef.
  PerfContext perf_context;
  #elif defined(ROCKSDB_SUPPORT_THREAD_LOCAL)
  #if defined(OS_SOLARIS)
  __thread PerfContext perf_context;
  #else   // OS_SOLARIS
  thread_local PerfContext perf_context;
  #endif  // OS_SOLARIS
  #else
  #error "No thread-local support. Disable perf context with -DNPERF_CONTEXT."
  #endif
  
  PerfContext* get_perf_context() {
    return &perf_context;
  }
  
  PerfContext::~PerfContext() {
  #if !defined(NPERF_CONTEXT) && defined(ROCKSDB_SUPPORT_THREAD_LOCAL) && !defined(OS_SOLARIS)
    ClearPerLevelPerfContext();
  #endif
  }
  
  PerfContext::PerfContext(const PerfContext& other) {
  #ifdef NPERF_CONTEXT
    (void)other;
  #else
    user_key_comparison_count = other.user_key_comparison_count;
    block_cache_hit_count = other.block_cache_hit_count;
    block_read_count = other.block_read_count;
    block_read_byte = other.block_read_byte;
    block_read_time = other.block_read_time;
    block_cache_index_hit_count = other.block_cache_index_hit_count;
    index_block_read_count = other.index_block_read_count;
    block_cache_filter_hit_count = other.block_cache_filter_hit_count;
    filter_block_read_count = other.filter_block_read_count;
    compression_dict_block_read_count = other.compression_dict_block_read_count;
    block_checksum_time = other.block_checksum_time;
    block_decompress_time = other.block_decompress_time;
    get_read_bytes = other.get_read_bytes;
    multiget_read_bytes = other.multiget_read_bytes;
    iter_read_bytes = other.iter_read_bytes;
    internal_key_skipped_count = other.internal_key_skipped_count;
    internal_delete_skipped_count = other.internal_delete_skipped_count;
    internal_recent_skipped_count = other.internal_recent_skipped_count;
    internal_merge_count = other.internal_merge_count;
    write_wal_time = other.write_wal_time;
    get_snapshot_time = other.get_snapshot_time;
    get_from_memtable_time = other.get_from_memtable_time;
    get_from_memtable_count = other.get_from_memtable_count;
    get_post_process_time = other.get_post_process_time;
    get_from_output_files_time = other.get_from_output_files_time;
    seek_on_memtable_time = other.seek_on_memtable_time;
    seek_on_memtable_count = other.seek_on_memtable_count;
    next_on_memtable_count = other.next_on_memtable_count;
    prev_on_memtable_count = other.prev_on_memtable_count;
    seek_child_seek_time = other.seek_child_seek_time;
    seek_child_seek_count = other.seek_child_seek_count;
    seek_min_heap_time = other.seek_min_heap_time;
    seek_internal_seek_time = other.seek_internal_seek_time;
    find_next_user_entry_time = other.find_next_user_entry_time;
    write_pre_and_post_process_time = other.write_pre_and_post_process_time;
    write_memtable_time = other.write_memtable_time;
    write_delay_time = other.write_delay_time;
    write_thread_wait_nanos = other.write_thread_wait_nanos;
    write_scheduling_flushes_compactions_time =
        other.write_scheduling_flushes_compactions_time;
    db_mutex_lock_nanos = other.db_mutex_lock_nanos;
    db_condition_wait_nanos = other.db_condition_wait_nanos;
    merge_operator_time_nanos = other.merge_operator_time_nanos;
    read_index_block_nanos = other.read_index_block_nanos;
    read_filter_block_nanos = other.read_filter_block_nanos;
    new_table_block_iter_nanos = other.new_table_block_iter_nanos;
    new_table_iterator_nanos = other.new_table_iterator_nanos;
    block_seek_nanos = other.block_seek_nanos;
    find_table_nanos = other.find_table_nanos;
    bloom_memtable_hit_count = other.bloom_memtable_hit_count;
    bloom_memtable_miss_count = other.bloom_memtable_miss_count;
    bloom_sst_hit_count = other.bloom_sst_hit_count;
    bloom_sst_miss_count = other.bloom_sst_miss_count;
    key_lock_wait_time = other.key_lock_wait_time;
    key_lock_wait_count = other.key_lock_wait_count;
  
    env_new_sequential_file_nanos = other.env_new_sequential_file_nanos;
    env_new_random_access_file_nanos = other.env_new_random_access_file_nanos;
    env_new_writable_file_nanos = other.env_new_writable_file_nanos;
    env_reuse_writable_file_nanos = other.env_reuse_writable_file_nanos;
    env_new_random_rw_file_nanos = other.env_new_random_rw_file_nanos;
    env_new_directory_nanos = other.env_new_directory_nanos;
    env_file_exists_nanos = other.env_file_exists_nanos;
    env_get_children_nanos = other.env_get_children_nanos;
    env_get_children_file_attributes_nanos =
        other.env_get_children_file_attributes_nanos;
    env_delete_file_nanos = other.env_delete_file_nanos;
    env_create_dir_nanos = other.env_create_dir_nanos;
    env_create_dir_if_missing_nanos = other.env_create_dir_if_missing_nanos;
    env_delete_dir_nanos = other.env_delete_dir_nanos;
    env_get_file_size_nanos = other.env_get_file_size_nanos;
    env_get_file_modification_time_nanos =
        other.env_get_file_modification_time_nanos;
    env_rename_file_nanos = other.env_rename_file_nanos;
    env_link_file_nanos = other.env_link_file_nanos;
    env_lock_file_nanos = other.env_lock_file_nanos;
    env_unlock_file_nanos = other.env_unlock_file_nanos;
    env_new_logger_nanos = other.env_new_logger_nanos;
    get_cpu_nanos = other.get_cpu_nanos;
    iter_next_cpu_nanos = other.iter_next_cpu_nanos;
    iter_prev_cpu_nanos = other.iter_prev_cpu_nanos;
    iter_seek_cpu_nanos = other.iter_seek_cpu_nanos;
    if (per_level_perf_context_enabled && level_to_perf_context != nullptr) {
      ClearPerLevelPerfContext();
    }
    if (other.level_to_perf_context != nullptr) {
      level_to_perf_context = new std::map<uint32_t, PerfContextByLevel>();
      *level_to_perf_context = *other.level_to_perf_context;
    }
    per_level_perf_context_enabled = other.per_level_perf_context_enabled;
  #endif
  }
  
  PerfContext::PerfContext(PerfContext&& other) noexcept {
  #ifdef NPERF_CONTEXT
    (void)other;
  #else
    user_key_comparison_count = other.user_key_comparison_count;
    block_cache_hit_count = other.block_cache_hit_count;
    block_read_count = other.block_read_count;
    block_read_byte = other.block_read_byte;
    block_read_time = other.block_read_time;
    block_cache_index_hit_count = other.block_cache_index_hit_count;
    index_block_read_count = other.index_block_read_count;
    block_cache_filter_hit_count = other.block_cache_filter_hit_count;
    filter_block_read_count = other.filter_block_read_count;
    compression_dict_block_read_count = other.compression_dict_block_read_count;
    block_checksum_time = other.block_checksum_time;
    block_decompress_time = other.block_decompress_time;
    get_read_bytes = other.get_read_bytes;
    multiget_read_bytes = other.multiget_read_bytes;
    iter_read_bytes = other.iter_read_bytes;
    internal_key_skipped_count = other.internal_key_skipped_count;
    internal_delete_skipped_count = other.internal_delete_skipped_count;
    internal_recent_skipped_count = other.internal_recent_skipped_count;
    internal_merge_count = other.internal_merge_count;
    write_wal_time = other.write_wal_time;
    get_snapshot_time = other.get_snapshot_time;
    get_from_memtable_time = other.get_from_memtable_time;
    get_from_memtable_count = other.get_from_memtable_count;
    get_post_process_time = other.get_post_process_time;
    get_from_output_files_time = other.get_from_output_files_time;
    seek_on_memtable_time = other.seek_on_memtable_time;
    seek_on_memtable_count = other.seek_on_memtable_count;
    next_on_memtable_count = other.next_on_memtable_count;
    prev_on_memtable_count = other.prev_on_memtable_count;
    seek_child_seek_time = other.seek_child_seek_time;
    seek_child_seek_count = other.seek_child_seek_count;
    seek_min_heap_time = other.seek_min_heap_time;
    seek_internal_seek_time = other.seek_internal_seek_time;
    find_next_user_entry_time = other.find_next_user_entry_time;
    write_pre_and_post_process_time = other.write_pre_and_post_process_time;
    write_memtable_time = other.write_memtable_time;
    write_delay_time = other.write_delay_time;
    write_thread_wait_nanos = other.write_thread_wait_nanos;
    write_scheduling_flushes_compactions_time =
        other.write_scheduling_flushes_compactions_time;
    db_mutex_lock_nanos = other.db_mutex_lock_nanos;
    db_condition_wait_nanos = other.db_condition_wait_nanos;
    merge_operator_time_nanos = other.merge_operator_time_nanos;
    read_index_block_nanos = other.read_index_block_nanos;
    read_filter_block_nanos = other.read_filter_block_nanos;
    new_table_block_iter_nanos = other.new_table_block_iter_nanos;
    new_table_iterator_nanos = other.new_table_iterator_nanos;
    block_seek_nanos = other.block_seek_nanos;
    find_table_nanos = other.find_table_nanos;
    bloom_memtable_hit_count = other.bloom_memtable_hit_count;
    bloom_memtable_miss_count = other.bloom_memtable_miss_count;
    bloom_sst_hit_count = other.bloom_sst_hit_count;
    bloom_sst_miss_count = other.bloom_sst_miss_count;
    key_lock_wait_time = other.key_lock_wait_time;
    key_lock_wait_count = other.key_lock_wait_count;
  
    env_new_sequential_file_nanos = other.env_new_sequential_file_nanos;
    env_new_random_access_file_nanos = other.env_new_random_access_file_nanos;
    env_new_writable_file_nanos = other.env_new_writable_file_nanos;
    env_reuse_writable_file_nanos = other.env_reuse_writable_file_nanos;
    env_new_random_rw_file_nanos = other.env_new_random_rw_file_nanos;
    env_new_directory_nanos = other.env_new_directory_nanos;
    env_file_exists_nanos = other.env_file_exists_nanos;
    env_get_children_nanos = other.env_get_children_nanos;
    env_get_children_file_attributes_nanos =
        other.env_get_children_file_attributes_nanos;
    env_delete_file_nanos = other.env_delete_file_nanos;
    env_create_dir_nanos = other.env_create_dir_nanos;
    env_create_dir_if_missing_nanos = other.env_create_dir_if_missing_nanos;
    env_delete_dir_nanos = other.env_delete_dir_nanos;
    env_get_file_size_nanos = other.env_get_file_size_nanos;
    env_get_file_modification_time_nanos =
        other.env_get_file_modification_time_nanos;
    env_rename_file_nanos = other.env_rename_file_nanos;
    env_link_file_nanos = other.env_link_file_nanos;
    env_lock_file_nanos = other.env_lock_file_nanos;
    env_unlock_file_nanos = other.env_unlock_file_nanos;
    env_new_logger_nanos = other.env_new_logger_nanos;
    get_cpu_nanos = other.get_cpu_nanos;
    iter_next_cpu_nanos = other.iter_next_cpu_nanos;
    iter_prev_cpu_nanos = other.iter_prev_cpu_nanos;
    iter_seek_cpu_nanos = other.iter_seek_cpu_nanos;
    if (per_level_perf_context_enabled && level_to_perf_context != nullptr) {
      ClearPerLevelPerfContext();
    }
    if (other.level_to_perf_context != nullptr) {
      level_to_perf_context = other.level_to_perf_context;
      other.level_to_perf_context = nullptr;
    }
    per_level_perf_context_enabled = other.per_level_perf_context_enabled;
  #endif
  }
  
  // TODO(Zhongyi): reduce code duplication between copy constructor and
  // assignment operator
  PerfContext& PerfContext::operator=(const PerfContext& other) {
  #ifdef NPERF_CONTEXT
    (void)other;
  #else
    user_key_comparison_count = other.user_key_comparison_count;
    block_cache_hit_count = other.block_cache_hit_count;
    block_read_count = other.block_read_count;
    block_read_byte = other.block_read_byte;
    block_read_time = other.block_read_time;
    block_cache_index_hit_count = other.block_cache_index_hit_count;
    index_block_read_count = other.index_block_read_count;
    block_cache_filter_hit_count = other.block_cache_filter_hit_count;
    filter_block_read_count = other.filter_block_read_count;
    compression_dict_block_read_count = other.compression_dict_block_read_count;
    block_checksum_time = other.block_checksum_time;
    block_decompress_time = other.block_decompress_time;
    get_read_bytes = other.get_read_bytes;
    multiget_read_bytes = other.multiget_read_bytes;
    iter_read_bytes = other.iter_read_bytes;
    internal_key_skipped_count = other.internal_key_skipped_count;
    internal_delete_skipped_count = other.internal_delete_skipped_count;
    internal_recent_skipped_count = other.internal_recent_skipped_count;
    internal_merge_count = other.internal_merge_count;
    write_wal_time = other.write_wal_time;
    get_snapshot_time = other.get_snapshot_time;
    get_from_memtable_time = other.get_from_memtable_time;
    get_from_memtable_count = other.get_from_memtable_count;
    get_post_process_time = other.get_post_process_time;
    get_from_output_files_time = other.get_from_output_files_time;
    seek_on_memtable_time = other.seek_on_memtable_time;
    seek_on_memtable_count = other.seek_on_memtable_count;
    next_on_memtable_count = other.next_on_memtable_count;
    prev_on_memtable_count = other.prev_on_memtable_count;
    seek_child_seek_time = other.seek_child_seek_time;
    seek_child_seek_count = other.seek_child_seek_count;
    seek_min_heap_time = other.seek_min_heap_time;
    seek_internal_seek_time = other.seek_internal_seek_time;
    find_next_user_entry_time = other.find_next_user_entry_time;
    write_pre_and_post_process_time = other.write_pre_and_post_process_time;
    write_memtable_time = other.write_memtable_time;
    write_delay_time = other.write_delay_time;
    write_thread_wait_nanos = other.write_thread_wait_nanos;
    write_scheduling_flushes_compactions_time =
        other.write_scheduling_flushes_compactions_time;
    db_mutex_lock_nanos = other.db_mutex_lock_nanos;
    db_condition_wait_nanos = other.db_condition_wait_nanos;
    merge_operator_time_nanos = other.merge_operator_time_nanos;
    read_index_block_nanos = other.read_index_block_nanos;
    read_filter_block_nanos = other.read_filter_block_nanos;
    new_table_block_iter_nanos = other.new_table_block_iter_nanos;
    new_table_iterator_nanos = other.new_table_iterator_nanos;
    block_seek_nanos = other.block_seek_nanos;
    find_table_nanos = other.find_table_nanos;
    bloom_memtable_hit_count = other.bloom_memtable_hit_count;
    bloom_memtable_miss_count = other.bloom_memtable_miss_count;
    bloom_sst_hit_count = other.bloom_sst_hit_count;
    bloom_sst_miss_count = other.bloom_sst_miss_count;
    key_lock_wait_time = other.key_lock_wait_time;
    key_lock_wait_count = other.key_lock_wait_count;
  
    env_new_sequential_file_nanos = other.env_new_sequential_file_nanos;
    env_new_random_access_file_nanos = other.env_new_random_access_file_nanos;
    env_new_writable_file_nanos = other.env_new_writable_file_nanos;
    env_reuse_writable_file_nanos = other.env_reuse_writable_file_nanos;
    env_new_random_rw_file_nanos = other.env_new_random_rw_file_nanos;
    env_new_directory_nanos = other.env_new_directory_nanos;
    env_file_exists_nanos = other.env_file_exists_nanos;
    env_get_children_nanos = other.env_get_children_nanos;
    env_get_children_file_attributes_nanos =
        other.env_get_children_file_attributes_nanos;
    env_delete_file_nanos = other.env_delete_file_nanos;
    env_create_dir_nanos = other.env_create_dir_nanos;
    env_create_dir_if_missing_nanos = other.env_create_dir_if_missing_nanos;
    env_delete_dir_nanos = other.env_delete_dir_nanos;
    env_get_file_size_nanos = other.env_get_file_size_nanos;
    env_get_file_modification_time_nanos =
        other.env_get_file_modification_time_nanos;
    env_rename_file_nanos = other.env_rename_file_nanos;
    env_link_file_nanos = other.env_link_file_nanos;
    env_lock_file_nanos = other.env_lock_file_nanos;
    env_unlock_file_nanos = other.env_unlock_file_nanos;
    env_new_logger_nanos = other.env_new_logger_nanos;
    get_cpu_nanos = other.get_cpu_nanos;
    iter_next_cpu_nanos = other.iter_next_cpu_nanos;
    iter_prev_cpu_nanos = other.iter_prev_cpu_nanos;
    iter_seek_cpu_nanos = other.iter_seek_cpu_nanos;
    if (per_level_perf_context_enabled && level_to_perf_context != nullptr) {
      ClearPerLevelPerfContext();
    }
    if (other.level_to_perf_context != nullptr) {
      level_to_perf_context = new std::map<uint32_t, PerfContextByLevel>();
      *level_to_perf_context = *other.level_to_perf_context;
    }
    per_level_perf_context_enabled = other.per_level_perf_context_enabled;
  #endif
    return *this;
  }
  
  void PerfContext::Reset() {
  #ifndef NPERF_CONTEXT
    user_key_comparison_count = 0;
    block_cache_hit_count = 0;
    block_read_count = 0;
    block_read_byte = 0;
    block_read_time = 0;
    block_cache_index_hit_count = 0;
    index_block_read_count = 0;
    block_cache_filter_hit_count = 0;
    filter_block_read_count = 0;
    compression_dict_block_read_count = 0;
    block_checksum_time = 0;
    block_decompress_time = 0;
    get_read_bytes = 0;
    multiget_read_bytes = 0;
    iter_read_bytes = 0;
    internal_key_skipped_count = 0;
    internal_delete_skipped_count = 0;
    internal_recent_skipped_count = 0;
    internal_merge_count = 0;
    write_wal_time = 0;
  
    get_snapshot_time = 0;
    get_from_memtable_time = 0;
    get_from_memtable_count = 0;
    get_post_process_time = 0;
    get_from_output_files_time = 0;
    seek_on_memtable_time = 0;
    seek_on_memtable_count = 0;
    next_on_memtable_count = 0;
    prev_on_memtable_count = 0;
    seek_child_seek_time = 0;
    seek_child_seek_count = 0;
    seek_min_heap_time = 0;
    seek_internal_seek_time = 0;
    find_next_user_entry_time = 0;
    write_pre_and_post_process_time = 0;
    write_memtable_time = 0;
    write_delay_time = 0;
    write_thread_wait_nanos = 0;
    write_scheduling_flushes_compactions_time = 0;
    db_mutex_lock_nanos = 0;
    db_condition_wait_nanos = 0;
    merge_operator_time_nanos = 0;
    read_index_block_nanos = 0;
    read_filter_block_nanos = 0;
    new_table_block_iter_nanos = 0;
    new_table_iterator_nanos = 0;
    block_seek_nanos = 0;
    find_table_nanos = 0;
    bloom_memtable_hit_count = 0;
    bloom_memtable_miss_count = 0;
    bloom_sst_hit_count = 0;
    bloom_sst_miss_count = 0;
    key_lock_wait_time = 0;
    key_lock_wait_count = 0;
  
    env_new_sequential_file_nanos = 0;
    env_new_random_access_file_nanos = 0;
    env_new_writable_file_nanos = 0;
    env_reuse_writable_file_nanos = 0;
    env_new_random_rw_file_nanos = 0;
    env_new_directory_nanos = 0;
    env_file_exists_nanos = 0;
    env_get_children_nanos = 0;
    env_get_children_file_attributes_nanos = 0;
    env_delete_file_nanos = 0;
    env_create_dir_nanos = 0;
    env_create_dir_if_missing_nanos = 0;
    env_delete_dir_nanos = 0;
    env_get_file_size_nanos = 0;
    env_get_file_modification_time_nanos = 0;
    env_rename_file_nanos = 0;
    env_link_file_nanos = 0;
    env_lock_file_nanos = 0;
    env_unlock_file_nanos = 0;
    env_new_logger_nanos = 0;
    get_cpu_nanos = 0;
    iter_next_cpu_nanos = 0;
    iter_prev_cpu_nanos = 0;
    iter_seek_cpu_nanos = 0;
    if (per_level_perf_context_enabled && level_to_perf_context) {
      for (auto& kv : *level_to_perf_context) {
        kv.second.Reset();
      }
    }
  #endif
  }
  
  #define PERF_CONTEXT_OUTPUT(counter)             \
    if (!exclude_zero_counters || (counter > 0)) { \
      ss << #counter << " = " << counter << ", ";  \
    }
  
  #define PERF_CONTEXT_BY_LEVEL_OUTPUT_ONE_COUNTER(counter)         \
    if (per_level_perf_context_enabled && \
        level_to_perf_context) {                                    \
      ss << #counter << " = ";                                      \
      for (auto& kv : *level_to_perf_context) {                     \
        if (!exclude_zero_counters || (kv.second.counter > 0)) {    \
          ss << kv.second.counter << "@level" << kv.first << ", ";  \
        }                                                           \
      }                                                             \
    }
  
  void PerfContextByLevel::Reset() {
  #ifndef NPERF_CONTEXT
    bloom_filter_useful = 0;
    bloom_filter_full_positive = 0;
    bloom_filter_full_true_positive = 0;
    block_cache_hit_count = 0;
    block_cache_miss_count = 0;
  #endif
  }
  
  std::string PerfContext::ToString(bool exclude_zero_counters) const {
  #ifdef NPERF_CONTEXT
    (void)exclude_zero_counters;
    return "";
  #else
    std::ostringstream ss;
    PERF_CONTEXT_OUTPUT(user_key_comparison_count);
    PERF_CONTEXT_OUTPUT(block_cache_hit_count);
    PERF_CONTEXT_OUTPUT(block_read_count);
    PERF_CONTEXT_OUTPUT(block_read_byte);
    PERF_CONTEXT_OUTPUT(block_read_time);
    PERF_CONTEXT_OUTPUT(block_cache_index_hit_count);
    PERF_CONTEXT_OUTPUT(index_block_read_count);
    PERF_CONTEXT_OUTPUT(block_cache_filter_hit_count);
    PERF_CONTEXT_OUTPUT(filter_block_read_count);
    PERF_CONTEXT_OUTPUT(compression_dict_block_read_count);
    PERF_CONTEXT_OUTPUT(block_checksum_time);
    PERF_CONTEXT_OUTPUT(block_decompress_time);
    PERF_CONTEXT_OUTPUT(get_read_bytes);
    PERF_CONTEXT_OUTPUT(multiget_read_bytes);
    PERF_CONTEXT_OUTPUT(iter_read_bytes);
    PERF_CONTEXT_OUTPUT(internal_key_skipped_count);
    PERF_CONTEXT_OUTPUT(internal_delete_skipped_count);
    PERF_CONTEXT_OUTPUT(internal_recent_skipped_count);
    PERF_CONTEXT_OUTPUT(internal_merge_count);
    PERF_CONTEXT_OUTPUT(write_wal_time);
    PERF_CONTEXT_OUTPUT(get_snapshot_time);
    PERF_CONTEXT_OUTPUT(get_from_memtable_time);
    PERF_CONTEXT_OUTPUT(get_from_memtable_count);
    PERF_CONTEXT_OUTPUT(get_post_process_time);
    PERF_CONTEXT_OUTPUT(get_from_output_files_time);
    PERF_CONTEXT_OUTPUT(seek_on_memtable_time);
    PERF_CONTEXT_OUTPUT(seek_on_memtable_count);
    PERF_CONTEXT_OUTPUT(next_on_memtable_count);
    PERF_CONTEXT_OUTPUT(prev_on_memtable_count);
    PERF_CONTEXT_OUTPUT(seek_child_seek_time);
    PERF_CONTEXT_OUTPUT(seek_child_seek_count);
    PERF_CONTEXT_OUTPUT(seek_min_heap_time);
    PERF_CONTEXT_OUTPUT(seek_internal_seek_time);
    PERF_CONTEXT_OUTPUT(find_next_user_entry_time);
    PERF_CONTEXT_OUTPUT(write_pre_and_post_process_time);
    PERF_CONTEXT_OUTPUT(write_memtable_time);
    PERF_CONTEXT_OUTPUT(write_thread_wait_nanos);
    PERF_CONTEXT_OUTPUT(write_scheduling_flushes_compactions_time);
    PERF_CONTEXT_OUTPUT(db_mutex_lock_nanos);
    PERF_CONTEXT_OUTPUT(db_condition_wait_nanos);
    PERF_CONTEXT_OUTPUT(merge_operator_time_nanos);
    PERF_CONTEXT_OUTPUT(write_delay_time);
    PERF_CONTEXT_OUTPUT(read_index_block_nanos);
    PERF_CONTEXT_OUTPUT(read_filter_block_nanos);
    PERF_CONTEXT_OUTPUT(new_table_block_iter_nanos);
    PERF_CONTEXT_OUTPUT(new_table_iterator_nanos);
    PERF_CONTEXT_OUTPUT(block_seek_nanos);
    PERF_CONTEXT_OUTPUT(find_table_nanos);
    PERF_CONTEXT_OUTPUT(bloom_memtable_hit_count);
    PERF_CONTEXT_OUTPUT(bloom_memtable_miss_count);
    PERF_CONTEXT_OUTPUT(bloom_sst_hit_count);
    PERF_CONTEXT_OUTPUT(bloom_sst_miss_count);
    PERF_CONTEXT_OUTPUT(key_lock_wait_time);
    PERF_CONTEXT_OUTPUT(key_lock_wait_count);
    PERF_CONTEXT_OUTPUT(env_new_sequential_file_nanos);
    PERF_CONTEXT_OUTPUT(env_new_random_access_file_nanos);
    PERF_CONTEXT_OUTPUT(env_new_writable_file_nanos);
    PERF_CONTEXT_OUTPUT(env_reuse_writable_file_nanos);
    PERF_CONTEXT_OUTPUT(env_new_random_rw_file_nanos);
    PERF_CONTEXT_OUTPUT(env_new_directory_nanos);
    PERF_CONTEXT_OUTPUT(env_file_exists_nanos);
    PERF_CONTEXT_OUTPUT(env_get_children_nanos);
    PERF_CONTEXT_OUTPUT(env_get_children_file_attributes_nanos);
    PERF_CONTEXT_OUTPUT(env_delete_file_nanos);
    PERF_CONTEXT_OUTPUT(env_create_dir_nanos);
    PERF_CONTEXT_OUTPUT(env_create_dir_if_missing_nanos);
    PERF_CONTEXT_OUTPUT(env_delete_dir_nanos);
    PERF_CONTEXT_OUTPUT(env_get_file_size_nanos);
    PERF_CONTEXT_OUTPUT(env_get_file_modification_time_nanos);
    PERF_CONTEXT_OUTPUT(env_rename_file_nanos);
    PERF_CONTEXT_OUTPUT(env_link_file_nanos);
    PERF_CONTEXT_OUTPUT(env_lock_file_nanos);
    PERF_CONTEXT_OUTPUT(env_unlock_file_nanos);
    PERF_CONTEXT_OUTPUT(env_new_logger_nanos);
    PERF_CONTEXT_OUTPUT(get_cpu_nanos);
    PERF_CONTEXT_OUTPUT(iter_next_cpu_nanos);
    PERF_CONTEXT_OUTPUT(iter_prev_cpu_nanos);
    PERF_CONTEXT_OUTPUT(iter_seek_cpu_nanos);
    PERF_CONTEXT_BY_LEVEL_OUTPUT_ONE_COUNTER(bloom_filter_useful);
    PERF_CONTEXT_BY_LEVEL_OUTPUT_ONE_COUNTER(bloom_filter_full_positive);
    PERF_CONTEXT_BY_LEVEL_OUTPUT_ONE_COUNTER(bloom_filter_full_true_positive);
    PERF_CONTEXT_BY_LEVEL_OUTPUT_ONE_COUNTER(block_cache_hit_count);
    PERF_CONTEXT_BY_LEVEL_OUTPUT_ONE_COUNTER(block_cache_miss_count);
  
    std::string str = ss.str();
    str.erase(str.find_last_not_of(", ") + 1);
    return str;
  #endif
  }
  
  void PerfContext::EnablePerLevelPerfContext() {
    if (level_to_perf_context == nullptr) {
      level_to_perf_context = new std::map<uint32_t, PerfContextByLevel>();
    }
    per_level_perf_context_enabled = true;
  }
  
  void PerfContext::DisablePerLevelPerfContext(){
    per_level_perf_context_enabled = false;
  }
  
  void PerfContext::ClearPerLevelPerfContext(){
    if (level_to_perf_context != nullptr) {
      level_to_perf_context->clear();
      delete level_to_perf_context;
      level_to_perf_context = nullptr;
    }
    per_level_perf_context_enabled = false;
  }
  
  }  // namespace ROCKSDB_NAMESPACE
  