Got errors when multiple publishers send lots of messages to a single subscriber

[terry-xiaoyu]

Branch: master
Erlang/OTP: ?

client(289): EXIT for function_clause
=CRASH REPORT==== 21-Dec-2020::20:28:35.747908 ===
  crasher:
    initial call: emqtt:init/1
    pid: <0.533.0>
    registered_name: []
    exception exit: function_clause
      in function  gen_statem:loop_state_callback_result/11 (gen_statem.erl, line 1291)
    ancestors: [<0.532.0>]
    message_queue_len: 0
    messages: []
    links: [<0.532.0>]
    dictionary: [{rand_seed,{#{jump => #Fun<rand.3.8986388>,
                                max => 288230376151711743,
                                next => #Fun<rand.2.8986388>,type => exsplus},
                              [49031399363660467|245356732546424851]}}]
    trap_exit: true
    status: running
    heap_size: 6772
    stack_size: 27
    reductions: 15106
  neighbours:

=ERROR REPORT==== 21-Dec-2020::20:28:35.752960 ===
** State machine <0.531.0> terminating
** Last event = {info,{tcp,#Port<0.638>,
                           <<48,10,0,3,109,115,103,104,101,108,108,111>>}}
** When server state  = {connected,
                            {state,undefined,<0.530.0>,undefined,"localhost",
                                1883,[],emqtt_sock,#Port<0.638>,[],60000,
                                false,
                                <<"emqtt-jaylin-XPS-playgorund-bfa60544ec4098915c5a">>,
                                true,undefined,undefined,4,<<"MQTT">>,300,
                                #Ref<0.3799365730.2466250753.176101>,false,
                                false,false,
                                {mqtt_msg,0,false,false,undefined,undefined,
                                    undefined,undefined},
                                #{},[],
                                #{<<"msg">> =>
                                      #{nl => 0,qos => 0,rap => 0,rh => 0}},
                                infinity,#{},#{},true,30000,
                                #Ref<0.3799365730.2466250763.174070>,30000,
                                undefined,0,3,#Fun<emqtt_frame.3.64202024>}}
** Reason for termination = exit:function_clause
** Callback mode = state_functions
** Stacktrace =
**  [{gen_statem,loop_state_callback_result,11,
                 [{file,"gen_statem.erl"},{line,1291}]},
     {proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,249}]}]

client(290): EXIT for function_clause
=CRASH REPORT==== 21-Dec-2020::20:28:35.753504 ===
  crasher:
    initial call: emqtt:init/1
    pid: <0.531.0>
    registered_name: []
    exception exit: function_clause
      in function  gen_statem:loop_state_callback_result/11 (gen_statem.erl, line 1291)
    ancestors: [<0.530.0>]
    message_queue_len: 0
    messages: []
    links: [<0.530.0>]
    dictionary: [{rand_seed,{#{jump => #Fun<rand.3.8986388>,
                                max => 288230376151711743,
                                next => #Fun<rand.2.8986388>,type => exsplus},
                              [265253399633761026|65008456749205848]}}]
    trap_exit: true
    status: running
    heap_size: 6772
    stack_size: 27
    reductions: 15106
  neighbours:

=ERROR REPORT==== 21-Dec-2020::20:28:35.759330 ===
** State machine <0.543.0> terminating
** Last event = {info,{tcp,#Port<0.656>,
                           <<48,10,0,3,109,115,103,104,101,108,108,111>>}}
** When server state  = {connected,
                            {state,undefined,<0.542.0>,undefined,"localhost",
                                1883,[],emqtt_sock,#Port<0.656>,[],60000,
                                false,
                                <<"emqtt-jaylin-XPS-playgorund-3fe1970d332938b8e46f">>,
                                true,undefined,undefined,4,<<"MQTT">>,300,
                                #Ref<0.3799365730.2466250753.176130>,false,
                                false,false,
                                {mqtt_msg,0,false,false,undefined,undefined,
                                    undefined,undefined},
                                #{},[],
                                #{<<"msg">> =>
                                      #{nl => 0,qos => 0,rap => 0,rh => 0}},
                                infinity,#{},#{},true,30000,
                                #Ref<0.3799365730.2466250753.176136>,30000,
                                undefined,0,3,#Fun<emqtt_frame.3.64202024>}}
** Reason for termination = exit:function_clause
** Callback mode = state_functions
** Stacktrace =
**  [{gen_statem,loop_state_callback_result,11,
                 [{file,"gen_statem.erl"},{line,1291}]},
     {proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,249}]}]

client(284): EXIT for function_clause
=CRASH REPORT==== 21-Dec-2020::20:28:35.759804 ===
  crasher:
    initial call: emqtt:init/1
    pid: <0.543.0>
    registered_name: []
    exception exit: function_clause
      in function  gen_statem:loop_state_callback_result/11 (gen_statem.erl, line 1291)
    ancestors: [<0.542.0>]
    message_queue_len: 0
    messages: []
    links: [<0.542.0>]
    dictionary: [{rand_seed,{#{jump => #Fun<rand.3.8986388>,
                                max => 288230376151711743,
                                next => #Fun<rand.2.8986388>,type => exsplus},
                              [265163363309778587|265634946921655764]}}]
    trap_exit: true
    status: running
    heap_size: 6772
    stack_size: 27
    reductions: 15106
  neighbours:

=ERROR REPORT==== 21-Dec-2020::20:28:35.761640 ===
** State machine <0.539.0> terminating
** Last event = {info,{tcp,#Port<0.650>,
                           <<48,10,0,3,109,115,103,104,101,108,108,111>>}}
** When server state  = {connected,
                            {state,undefined,<0.538.0>,undefined,"localhost",
                                1883,[],emqtt_sock,#Port<0.650>,[],60000,
                                false,
                                <<"emqtt-jaylin-XPS-playgorund-bf9d8556354edf5e660a">>,
                                true,undefined,undefined,4,<<"MQTT">>,300,
                                #Ref<0.3799365730.2466250763.174073>,false,
                                false,false,
                                {mqtt_msg,0,false,false,undefined,undefined,
                                    undefined,undefined},
                                #{},[],
                                #{<<"msg">> =>
                                      #{nl => 0,qos => 0,rap => 0,rh => 0}},
                                infinity,#{},#{},true,30000,
                                #Ref<0.3799365730.2466250763.174081>,30000,
                                undefined,0,3,#Fun<emqtt_frame.3.64202024>}}
** Reason for termination = exit:function_clause
** Callback mode = state_functions
** Stacktrace =
**  [{gen_statem,loop_state_callback_result,11,
                 [{file,"gen_statem.erl"},{line,1291}]},
     {proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,249}]}]

[terry-xiaoyu]

Logs are too short to investigate the problem, we have to make it longer first.