mbarekTrismegistus

Tsung load test stuck exactly at 5000 connected users

<?xml version="1.0"?>
<!DOCTYPE tsung SYSTEM "tsung-1.0.dtd">
<tsung loglevel="warning" version="1.0">
  
  <clients>
    <client host="localhost" use_controller_vm="true" maxusers="60000"/>
  </clients>
  
  <servers>
    <server host="141.145.208.139" port="4000" type="tcp"/>
  </servers>
  
  <load>
    <arrivalphase phase="1" duration="400" unit="second">
      <users maxnumber="60000" arrivalrate="500" unit="second"/>
    </arrivalphase>
  </load>
  
  <options>
    <option name="ports_range" min="1025" max="65535"/>
  </options>
  
  <sessions>
    <session name="websocket" probability="100" type="ts_websocket">
      
      <request>
        <websocket type="connect" path="/socket/websocket"/>
      </request>
      
      <request>
        <websocket type="message">{"topic":"conversation:83","event":"phx_join","payload":{},"ref":"1"}</websocket>
      </request>
      
      <for var="i" from="1" to="1000" incr="1">
        <thinktime value="30"/>
        <request>
          <websocket type="message">{"topic":"phoenix","event":"heartbeat","payload":{},"ref":"heartbeat"}</websocket>
        </request>
      </for>
      
    </session>
  </sessions>
</tsung>

what i tried:

increasing ulimit for both client and server

when i start the test i can see some increase in cpu in phoenix service cpu usage and is logs the connected message and join the topic, then stops

this is the logs of tsung:

stats: dump at 1772737296

stats: users 4466 4466
stats: {cpu,“tsung_controller@unknown”} 1 23.92556014996428 0 23.92556014996428 23.92556014996428 0 0
stats: {load,“tsung_controller@unknown”} 1 0.30078125 0 0.30078125 0.30078125 0 0
stats: {freemem,“tsung_controller@unknown”} 1 5084.1953125 0 5084.1953125 5084.1953125 0 0
stats: users_count 4466 4466
stats: finish_users_count 0 0
stats: request 8380 65.26576169451066 24.256316804754 198.083 34.12 0 0
stats: connect 4229 40.902805864270455 4.201730056014052 60.217 34.467 0 0
stats: page 4177 130.49040052669372 17.767087540512446 248.559 105.436 0 0
stats: size_rcv 1329777 1329777
stats: size_sent 5318132 5318132
stats: connected 4229 4229
stats: websocket_succ 4203 4203

stats: dump at 1772737306

stats: users 9393 9393
stats: {cpu,“tsung_controller@unknown”} 1 18.802265983274886 0.0 23.92556014996428 18.802265983274886 23.92556014996428 1
stats: {load,“tsung_controller@unknown”} 1 0.25 0.0 0.30078125 0.25 0.30078125 1
stats: {freemem,“tsung_controller@unknown”} 1 4877.2734375 0.0 5084.1953125 4877.2734375 5084.1953125 1
stats: users_count 4927 9393
stats: finish_users_count 0 0
stats: request 1764 64.8651275510203 34.46547744678856 1127.223 34.12 65.26576169451066 8380
stats: connect 843 42.19985646500603 36.21356727868989 1084.529 34.467 40.902805864270455 4229
stats: page 895 130.3516491620113 37.330267446701676 1167.76 105.436 130.49040052669372 4177
stats: size_rcv 278047 1607824
stats: size_sent 1062444 6380576
stats: connected 843 5072
stats: websocket_succ 869 5072

stats: dump at 1772737316

stats: users 14204 14204
stats: {cpu,“tsung_controller@unknown”} 1 11.827101564571732 0.0 23.92556014996428 11.827101564571732 21.36391306661958 2
stats: {load,“tsung_controller@unknown”} 1 0.2890625 0.0 0.30078125 0.25 0.275390625 2
stats: {freemem,“tsung_controller@unknown”} 1 4617.7890625 0.0 5084.1953125 4617.7890625 4980.734375 2
stats: users_count 4811 14204
stats: finish_users_count 0 0
stats: request 2 561.432 523.1210000000001 1127.223 34.12 65.19609305993683 10144
stats: connect 1 1044.818 0.0 1084.529 34.467 41.11838426656148 5072
stats: page 1 1122.941 0.0 1167.76 105.436 130.46591660094634 5072
stats: size_rcv 317 1608141
stats: size_sent 1258 6381834
stats: connected 1 5073
stats: websocket_succ 1 5073

stats: dump at 1772737326

stats: users 17763 17763
stats: {cpu,“tsung_controller@unknown”} 1 10.584228451663611 0.0 23.92556014996428 10.584228451663611 18.1849758992703 3
stats: {load,“tsung_controller@unknown”} 1 0.3203125 0.0 0.3203125 0.25 0.2799479166666667 3
stats: {freemem,“tsung_controller@unknown”} 1 4332.6484375 0.0 5084.1953125 4332.6484375 4859.752604166667 3
stats: users_count 3559 17763
stats: finish_users_count 0 0
stats: request 4207 50.92889160922288 353.6956122984609 19550.499 34.12 65.29391208357964 10146
stats: size_rcv 416850 2024991
stats: connect 3 11651.867666666667 6268.992401118612 19507.13 34.467 41.3162355608121 5073
stats: page 4204 50.96614486203623 354.8746595210742 19597.113 34.146 130.66155529272618 5073
stats: size_sent 325178 6707012
stats: connected 3 5076
stats: websocket_succ 3 5076

stats: dump at 1772737336

stats: users 20868 20868
stats: {cpu,“tsung_controller@unknown”} 1 46.22984919396776 0.0 46.22984919396776 10.584228451663611 16.284789037368625 4
stats: {load,“tsung_controller@unknown”} 1 0.4296875 0.0 0.4296875 0.25 0.2900390625 4
stats: {freemem,“tsung_controller@unknown”} 1 4099.703125 0.0 5084.1953125 4099.703125 4727.9765625 4
stats: users_count 3105 20868
stats: finish_users_count 0 0
stats: request 871 41.58996900114803 4.761006355350374 19550.499 34.059 61.083388768898466 14353
stats: connect 0 0 0 19507.13 34.467 48.17826359338058 5076
stats: page 871 41.58996900114803 4.761006355350374 19597.113 34.059 94.54648517839821 9277
stats: size_rcv 86229 2111220
stats: size_sent 64068 6771080
stats: connected 0 5076
stats: websocket_succ 0 5076

stats: dump at 1772737346

stats: users 23648 23648
stats: {cpu,“tsung_controller@unknown”} 1 32.80853224987303 0.0 46.22984919396776 10.584228451663611 22.273801068688453 5
stats: {load,“tsung_controller@unknown”} 1 0.51953125 0.0 0.51953125 0.25 0.31796875 5
stats: {freemem,“tsung_controller@unknown”} 1 3922.98828125 0.0 5084.1953125 3922.98828125 4602.321875 5
stats: users_count 2780 23648
stats: finish_users_count 0 0
stats: request 19 2171.656894736842 3081.405941854377 19550.499 34.059 59.96812545980029 15224
stats: page 10 4126.455400000001 3216.7239622951856 19597.113 34.059 90.00124221521483 10148
stats: size_rcv 2952 2114172
stats: size_sent 11398 6782478
stats: connect 9 4489.216555555556 3070.07860660223 19507.13 34.467 48.17826359338058 5076
stats: connected 9 5085
stats: websocket_succ 9 5085

stats: dump at 1772737356

stats: users 27230 27230
stats: {cpu,“tsung_controller@unknown”} 1 32.48730964467005 0.0 46.22984919396776 10.584228451663611 24.02958959888588 6
stats: {load,“tsung_controller@unknown”} 1 0.44140625 0.0 0.51953125 0.25 0.3515625 6
stats: {freemem,“tsung_controller@unknown”} 1 3720.27734375 0.0 5084.1953125 3720.27734375 4489.099609375 6
stats: users_count 3582 27230
stats: finish_users_count 0 0
stats: request 4250 42.41863152941167 21.352453923474716 19550.499 34.059 62.6002901659778 15243
stats: page 4249 42.42863403153671 21.777244209394205 19597.113 34.059 93.97491238432764 10158
stats: connect 1 1054.813 0.0 19507.13 34.467 56.038508357915404 5085
stats: size_rcv 420869 2535041
stats: size_sent 325626 7108104
stats: connected 1 5086
stats: websocket_succ 1 5086

stats: dump at 1772737367

stats: users 28237 28249
stats: {cpu,“tsung_controller@unknown”} 1 48.11715481171548 0.0 48.11715481171548 10.584228451663611 25.23783531971219 7
stats: {load,“tsung_controller@unknown”} 1 0.609375 0.0 0.609375 0.25 0.36439732142857145 7
stats: {freemem,“tsung_controller@unknown”} 1 3482.6640625 0.0 5084.1953125 3482.6640625 4379.267857142857 7
stats: session 696 213.49577729885067 33.9491718719882 353.745 137.804 0 0
stats: users_count 1703 28933
stats: finish_users_count 696 696
stats: request 829 54.91196501809405 391.5845597034931 19550.499 34.059 58.20014400041036 19493
stats: page 828 54.97843357487919 393.45779514016743 19597.113 34.059 78.7725706948011 14407
stats: size_rcv 82190 2617231
stats: connect 1 11273.349 0.0 19507.13 34.467 56.234885568226474 5086
stats: error_connect_eaddrinuse 2794 2794
stats: size_sent 62590 7170694
stats: connected 1 5087
stats: websocket_succ 1 5087
stats: error_abort_max_conn_retries 691 691

now im stuck idk what’s wrong exactly pleas help

5 comments

/phoenix #deployment #testing #troubleshooting #learning-elixir

1 259 5

2026-03-07 15:20:37 UTC

Marked As Solved

mbarekTrismegistus

okay, guys turned out that a test from a local machine was a bad idea, i tested in the same vps im hosting phoenix in, and it handles it perfectly, it’s a 4ocpu, 24gb ram vps, it only took 1gb ram in the test, and some cpu cuz the connect function had to decrypt a token, how much realistically i could handle in this machine ?