investigate flaky parallel/test-http-server-request-timeout-keepalive

[Trott]

• Test: parallel/test-http-server-request-timeout-keepalive
• Platform: Ubuntu 18.04 x64
• Console Output:

not ok 1236 parallel/test-http-server-request-timeout-keepalive
  ---
  duration_ms: 1.783
  severity: fail
  exitcode: 1
  stack: |-
    performRequestWithDelay 50 500
    node:assert:119
      throw new AssertionError(obj);
      ^
    
    AssertionError [ERR_ASSERTION]: Expected values to be strictly equal:
    + actual - expected
    
    + 'HTTP/1.1 408 Request Timeout'
    - 'HTTP/1.1 200 OK'
                ^
        at Socket.<anonymous> (/home/iojs/build/workspace/node-test-commit-linux/nodes/ubuntu1804-64/test/parallel/test-http-server-request-timeout-keepalive.js:56:14)
        at Socket.<anonymous> (/home/iojs/build/workspace/node-test-commit-linux/nodes/ubuntu1804-64/test/common/index.js:377:15)
        at Socket.emit (node:events:379:20)
        at addChunk (node:internal/streams/readable:311:12)
        at readableAddChunk (node:internal/streams/readable:286:9)
        at Socket.Readable.push (node:internal/streams/readable:225:10)
        at TCP.onStreamRead (node:internal/stream_base_commons:190:23) {
      generatedMessage: true,
      code: 'ERR_ASSERTION',
      actual: 'HTTP/1.1 408 Request Timeout',
      expected: 'HTTP/1.1 200 OK',
      operator: 'strictEqual'
    }
  ...

• Build Links: https://ci.nodejs.org/job/node-test-commit-linux/nodes=ubuntu1804-64/39255/consoleText

[Trott]

Still going on.

https://ci.nodejs.org/job/node-test-commit-linux/nodes=ubuntu1804-64/40003/testReport/junit/(root)/test/parallel_test_http_server_request_timeout_keepalive/

not ok 1250 parallel/test-http-server-request-timeout-keepalive
  ---
  duration_ms: 1.436
  severity: fail
  exitcode: 1
  stack: |-
    performRequestWithDelay 50 500
    node:assert:122
      throw new AssertionError(obj);
      ^
    
    AssertionError [ERR_ASSERTION]: Expected values to be strictly equal:
    + actual - expected
    
    + 'HTTP/1.1 408 Request Timeout'
    - 'HTTP/1.1 200 OK'
                ^
        at Socket.<anonymous> (/home/iojs/build/workspace/node-test-commit-linux/nodes/ubuntu1804-64/test/parallel/test-http-server-request-timeout-keepalive.js:56:14)
        at Socket.<anonymous> (/home/iojs/build/workspace/node-test-commit-linux/nodes/ubuntu1804-64/test/common/index.js:376:15)
        at Socket.emit (node:events:378:20)
        at addChunk (node:internal/streams/readable:321:12)
        at readableAddChunk (node:internal/streams/readable:296:9)
        at Socket.Readable.push (node:internal/streams/readable:235:10)
        at TCP.onStreamRead (node:internal/stream_base_commons:190:23) {
      generatedMessage: true,
      code: 'ERR_ASSERTION',
      actual: 'HTTP/1.1 408 Request Timeout',
      expected: 'HTTP/1.1 200 OK',
      operator: 'strictEqual'
    }
  ...