emqtt_bench doesn't send PINGREQ??

[JaylinYu]

when I doing the performance benchmark in the following scenario:
I7-6500U
8GB RAM
SYSTEM TUNED

with

./emqtt_bench sub -c 2000 -i 50 -t bench/111 -q 0 -k 10

then get:

client(1): EXIT for {disconnected,141,#{}}
=ERROR REPORT==== 13-Nov-2020::11:59:07.796452 ===
** State machine <0.4105.0> terminating
** Last event = {cast,{mqtt_packet,{mqtt_packet_header,14,false,0,false},
{mqtt_packet_disconnect,141,#{}},
undefined}}
** When server state = {connected,
{state,undefined,<0.4104.0>,undefined,
"localhost",1883,[],emqtt_sock,#Port<0.4005>,
[],60000,false,
<<"jaylin-Playground_bench_sub_1_1676407926">>,
true,undefined,undefined,5,<<"MQTT">>,10,
#Ref<0.1272275936.3838312449.192995>,false,
false,false,
{mqtt_msg,0,false,false,undefined,undefined,
undefined,undefined},
#{'Maximum-Packet-Size' => 1048576,
'Retain-Available' => 1,
'Shared-Subscription-Available' => 1,
'Subscription-Identifier-Available' => 1,
'Topic-Alias-Maximum' => 65535,
'Wildcard-Subscription-Available' => 1},
[],
#{<<"bench/111">> =>
#{nl => 0,qos => 0,rap => 0,rh => 0}},
infinity,#{},#{},true,30000,undefined,0,
undefined,0,5,
{none,#{max_size => 268435455,version => 5}}}}
** Reason for termination = exit:{disconnected,141,#{}}
** Callback mode = state_functions
** Stacktrace =
** [{gen_statem,loop_state_callback_result,11,
[{file,"gen_statem.erl"},{line,1298}]},
{proc_lib,wake_up,3,[{file,"proc_lib.erl"},{line,259}]}]

=CRASH REPORT==== 13-Nov-2020::11:59:07.798331 ===
crasher:
initial call: emqtt:init/1
pid: <0.4105.0>
registered_name: []
exception exit: {disconnected,141,#{}}
in function gen_statem:loop_state_callback_result/11 (gen_statem.erl, line 1298)
ancestors: [<0.4104.0>]
message_queue_len: 0
messages: []
links: [<0.4104.0>]
dictionary: [{send_oct,76}]
trap_exit: true
status: running
heap_size: 6772
stack_size: 27
reductions: 14923
neighbours:

[HJianBo]

Hi @JaylinYu Which version are you using? We'll try to reproduce it later.