PM2 error: read ENOTCONN

What's going wrong?

It looks like pm2 while restarting an app after error getting unexpected error itself. For now I don't understand what is going and how to replicate the issue. Maybe someone can explain me an error and give me some idea of the direction where to digg.

2022-03-31T22:08:58: PM2 log: App [strategy--mm--sub1:4740] starting in -fork mode-
2022-03-31T22:08:58: PM2 log: App [strategy--mm--sub1:4740] online
2022-03-31T22:29:02: PM2 log: App [strategy--mm--sub1:4740] exited with code [1] via signal [SIGINT]
2022-03-31T22:29:12: PM2 log: App [strategy--mm--sub1:4740] starting in -fork mode-
2022-03-31T22:29:12: PM2 log: App [strategy--mm--sub1:4740] online
2022-03-31T22:29:12: PM2 error: Error: spawn /usr/bin/python3 EAGAIN
    at Process.ChildProcess._handle.onexit (node:internal/child_process:282:19)
    at onErrorNT (node:internal/child_process:477:16)
    at processTicksAndRejections (node:internal/process/task_queues:83:21)
2022-03-31T22:29:12: PM2 log: ===============================================================================
2022-03-31T22:29:12: PM2 log: --- PM2 global error caught ---------------------------------------------------
2022-03-31T22:29:12: PM2 log: Time                 : Thu Mar 31 2022 22:29:12 GMT+0000 (Coordinated Universal Time)
2022-03-31T22:29:12: PM2 error: read ENOTCONN
2022-03-31T22:29:12: PM2 error: Error: read ENOTCONN
    at tryReadStart (node:net:592:20)
    at Socket._read (node:net:603:5)
    at Socket.Readable.read (node:internal/streams/readable:487:10)
    at Socket.read (node:net:644:39)
    at new Socket (node:net:401:12)
    at Object.Socket (node:net:284:41)
    at createSocket (node:internal/child_process:327:14)
    at ChildProcess.spawn (node:internal/child_process:444:23)
    at spawn (node:child_process:698:9)
    at /usr/lib/node_modules/pm2/lib/God/ForkMode.js:118:20
2022-03-31T22:29:12: PM2 log: ===============================================================================
2022-03-31T22:29:12: PM2 error: [PM2] Resurrecting PM2
node:events:368
      throw er; // Unhandled 'error' event
      ^

<ref *1> Error: read ENOTCONN
    at tryReadStart (node:net:592:20)
    at Socket._read (node:net:603:5)
    at Socket.Readable.read (node:internal/streams/readable:487:10)
    at Socket.read (node:net:644:39)
    at new Socket (node:net:401:12)
    at Object.Socket (node:net:284:41)
    at createSocket (node:internal/child_process:327:14)
    at ChildProcess.spawn (node:internal/child_process:444:23)
    at spawn (node:child_process:698:9)
    at /usr/lib/node_modules/pm2/lib/God/ForkMode.js:118:20
Emitted 'error' event on Domain instance at:
    at Socket.emit (node:domain:525:12)
    at emitErrorNT (node:internal/streams/destroy:157:8)
    at emitErrorCloseNT (node:internal/streams/destroy:122:3)
    at processTicksAndRejections (node:internal/process/task_queues:83:21) {
  errno: -107,
  code: 'ENOTCONN',
  syscall: 'read',
  domainEmitter: Socket {
    connecting: false,
    _hadError: false,
    _parent: null,
    _host: null,
    _readableState: ReadableState {
      objectMode: false,
      highWaterMark: 16384,
      buffer: BufferList { head: null, tail: null, length: 0 },
      length: 0,
      pipes: [],
      flowing: true,
      ended: false,
      endEmitted: false,
      reading: true,
      constructed: true,
      sync: false,
      needReadable: true,
      emittedReadable: false,
      readableListening: false,
      resumeScheduled: true,
      errorEmitted: true,
      emitClose: false,
      autoDestroy: true,
      destroyed: true,
      errored: [Circular *1],
      closed: true,
      closeEmitted: false,
      defaultEncoding: 'utf8',
      awaitDrainWriters: null,
      multiAwaitDrain: false,
      readingMore: false,
      dataEmitted: false,
      decoder: null,
      encoding: null,
      [Symbol(kPaused)]: false
    },
    _events: [Object: null prototype] {
      end: [Function: onReadableStreamEnd],
      close: [Function (anonymous)],
      data: [Function: forkErrData]
    },
    _eventsCount: 3,
    _maxListeners: undefined,
    _writableState: WritableState {
      objectMode: false,
      highWaterMark: 16384,
      finalCalled: false,
      needDrain: false,
      ending: false,
      ended: false,
      finished: false,
      destroyed: true,
      decodeStrings: false,
      defaultEncoding: 'utf8',
      length: 0,
      writing: false,
      corked: 0,
      sync: true,
      bufferProcessing: false,
      onwrite: [Function: bound onwrite],
      writecb: null,
      writelen: 0,
      afterWriteTickInfo: null,
      buffered: [],
      bufferedIndex: 0,
      allBuffers: true,
      allNoop: true,
      pendingcb: 0,
      constructed: true,
      prefinished: false,
      errorEmitted: true,
      emitClose: false,
      autoDestroy: true,
      errored: [Circular *1],
      closed: true,
      closeEmitted: false,
      writable: false,
      [Symbol(kOnFinished)]: []
    },
    allowHalfOpen: false,
    _sockname: null,
    _pendingData: null,
    _pendingEncoding: '',
    server: null,
    _server: null,
    [Symbol(async_id_symbol)]: 92180833,
    [Symbol(kHandle)]: null,
    [Symbol(kSetNoDelay)]: false,
    [Symbol(lastWriteQueueSize)]: 0,
    [Symbol(timeout)]: null,
    [Symbol(kBuffer)]: null,
    [Symbol(kBufferCb)]: null,
    [Symbol(kBufferGen)]: null,
    [Symbol(kCapture)]: false,
    [Symbol(kBytesRead)]: 0,
    [Symbol(kBytesWritten)]: 0
  },
  domainThrown: false
}

How could we reproduce this issue?

Right now have no idea.

Supporting information

--- PM2 report ----------------------------------------------------------------
Date                 : Fri Apr 01 2022 11:20:44 GMT+0000 (Coordinated Universal Time)
===============================================================================
--- Daemon -------------------------------------------------
pm2d version         : 5.1.2
node version         : 16.14.2
node path            : /usr/bin/pm2
argv                 : /usr/bin/node,/usr/lib/node_modules/pm2/lib/Daemon.js
argv0                : node
user                 : ec2-user
uid                  : 1000
gid                  : 1000
uptime               : 3min
===============================================================================
--- CLI ----------------------------------------------------
local pm2            : 5.1.2
node version         : 16.14.2
node path            : /usr/bin/pm2
argv                 : /usr/bin/node,/usr/bin/pm2,report
argv0                : node
user                 : ec2-user
uid                  : 1000
gid                  : 1000
===============================================================================
--- System info --------------------------------------------
arch                 : x64
platform             : linux
type                 : Linux
cpus                 : Intel(R) Xeon(R) Platinum 8124M CPU @ 3.00GHz
cpus nb              : 36
freemem              : 30082981888
totalmem             : 73638830080
home                 : /home/ec2-user
===============================================================================

The stack trace points to PM2's lib/God/ForkMode.js and Node.js child_process.spawn; start by tracing the restart path around the reported EAGAIN and ENOTCONN errors. Try to reproduce it with PM2 5.1.2, Node.js 16.14.2, and Linux; done means the failure has a reproducible cause and the daemon's restart behavior is verified.