anchor.diff:  -define(DEF_THRESHOLD_SLOW_PROC, 1000).
   
   -ifdef(TEST).
  --define(DEF_MIN_COMPACTION_WT, 10).   %% 10msec
  --define(DEF_REG_COMPACTION_WT, 100).  %% 100msec
  --define(DEF_MAX_COMPACTION_WT, 300).  %% 300msec
  +-define(DEF_MIN_COMPACTION_WT, 10).  %% 10msec
  +-define(DEF_REG_COMPACTION_WT, 100). %% 100msec
  +-define(DEF_MAX_COMPACTION_WT, 300). %% 300msec
   -define(DEF_COMPACTION_TIMEOUT, timer:minutes(1)). %% 1min
   -else.
   -define(DEF_MIN_COMPACTION_WT,  300). %% 300msec
  
positive.code: -define(DEF_REG_COMPACTION_BP,  50). %% 50
  -define(DEF_MAX_COMPACTION_BP, 150). %% 150
  -else.
  -define(DEF_MIN_COMPACTION_BP,   100). %%    100
  -define(DEF_REG_COMPACTION_BP,  1000). %%  1,000
  -define(DEF_MAX_COMPACTION_BP, 10000). %% 10,000
  -endif.
  
  
negative.code:                          ?OBJ_PRV_READ_ONLY |
                           ?OBJ_PRV_WRITE_ONLY).
  -record(obj_server_state, {
                             id :: atom(),
                             seq_num = 0 :: non_neg_integer(),
                             privilege = ?OBJ_PRV_READ_WRITE :: obj_privilege(),
                             meta_db_id :: atom(),
                             compaction_worker_id :: atom(),
                             diagnosis_logger_id :: atom(),
                             root_path = [] :: string(),
                             object_storage = #backend_info{}  :: #backend_info{},
                             storage_stats  = #storage_stats{} :: #storage_stats{},
                             state_filepath :: string(),
                             sync_mode = ?SYNC_MODE_NONE :: sync_mode(),
                             sync_interval_in_ms = ?DEF_SYNC_INTERVAL :: pos_integer(),
                             is_strict_check = false :: boolean(),
                             is_locked = false :: boolean(),
                             is_del_blocked = false  :: boolean(),
                             threshold_slow_processing = ?DEF_THRESHOLD_SLOW_PROC :: non_neg_integer(),
                             is_able_to_write = true :: boolean()
                            }).
  
  %% apllication-env
  -define(env_metadata_db(),
  