anchor.diff:  
       spawn_at_nodes(Workers, ThreadsNum, 1, TestFun2),
       OpsNum2 = DocsPerThead * ThreadsNum,
  -    {OkNum2, _OkTime2, ErrorNum2, _ErrorTime2} = count_answers(OpsNum2),
  -    ?assertEqual(0, ErrorNum2),
  +    {OkNum2, _OkTime2, _ErrorNum2, _ErrorTime2, ErrorsList2} = count_answers(OpsNum2),
  +    ?assertEqual([], ErrorsList2),
       ?assertEqual(OpsNum2, OkNum2),
   
       #parameter{name = save_time, value = OkTime/OkNum, unit = "microsek"}.
  
positive.code: 
      spawn_at_nodes(Workers, ThreadsNum, ConflictedThreads, TestFun2),
      OpsNum2 = DocsPerThead * ThreadsNum,
      {OkNum2, _OkTime2, ErrorNum2, _ErrorTime4} = count_answers(OpsNum2),
      ?assertEqual(0, ErrorNum2),
      ?assertEqual(OpsNum2, OkNum2),
  
      spawn_at_nodes(Workers, ThreadsNum, ConflictedThreads, TestFun),
      {OkNum3, OkTime3, ErrorNum3, _ErrorTime3} = count_answers(OpsNum),
      ?assertEqual(OpsNum, OkNum3),
      ?assertEqual(0, ErrorNum3),
  
      TestFun3 = fun(DocsSet) ->
          for(1, DocsPerThead, fun(I) ->
  
negative.code: 
      spawn_at_nodes(Workers, ThreadsNum, ConflictedThreads, TestFun2),
      OpsNum2 = DocsPerThead * ThreadsNum,
      {OkNum2, _OkTime2, _ErrorNum2, _ErrorTime2, ErrorsList2} = count_answers(OpsNum2),
      ?assertEqual([], ErrorsList2),
      ?assertEqual(OpsNum2, OkNum2),
  
      spawn_at_nodes(Workers, ThreadsNum, ConflictedThreads, TestFun),
      {OkNum3, OkTime3, _ErrorNum3, _ErrorTime3, ErrorsList3} = count_answers(OpsNum),
      ?assertEqual(OpsNum, OkNum3),
      ?assertEqual([], ErrorsList3),
  
      TestFun3 = fun(DocsSet) ->
          for(1, DocsPerThead, fun(I) ->
  