investigate flaky test-performance-eventlooputil

[Trott]

• Test: parllel/test-performance-eventlooputil
• Platform: centos7-64-gcc8
• Console Output:

09:46:55 not ok 1670 parallel/test-performance-eventlooputil
09:46:55 ---
09:46:55 duration_ms: 0.336
09:46:55 severity: fail
09:46:55 exitcode: 1
09:46:55 stack: |-
09:46:55 assert.js:385
09:46:55 throw err;
09:46:55 ^
09:46:55 
09:46:55 AssertionError [ERR_ASSERTION]: The expression evaluated to a falsy value:
09:46:55 
09:46:55 assert.ok(elu2.active > elu3.active)
09:46:55 
09:46:55 at Timeout._onTimeout (/home/iojs/build/workspace/node-test-commit-linux/nodes/centos7-64-gcc8/test/parallel/test-performance-eventlooputil.js:41:10)
09:46:55 at listOnTimeout (internal/timers.js:555:17)
09:46:55 at processTimers (internal/timers.js:498:7){
09:46:55 generatedMessage: true,
09:46:55 code: 'ERR_ASSERTION',
09:46:55 actual: false,
09:46:55 expected: true,
09:46:55 operator: '=='
09:46:55 }
09:46:55 ...

• Build Links:
  https://ci.nodejs.org/job/node-test-commit-linux/37149/nodes=centos7-64-gcc8/console

[Trott]

• Platform: ubuntu1804_sharedlibs_debug_x64
• Console Output:

00:14:39 not ok 1623 parallel/test-performance-eventlooputil
00:14:39 ---
00:14:39 duration_ms: 0.270
00:14:39 severity: fail
00:14:39 exitcode: 1
00:14:39 stack: |-
00:14:39 assert.js:386
00:14:39 throw err;
00:14:39 ^
00:14:39 
00:14:39 AssertionError [ERR_ASSERTION]: The expression evaluated to a falsy value:
00:14:39 
00:14:39 assert.ok(elu2.active > elu3.active)
00:14:39 
00:14:39 at Timeout._onTimeout (/home/iojs/build/workspace/node-test-commit-linux-containered/test/parallel/test-performance-eventlooputil.js:41:10)
00:14:39 at listOnTimeout (internal/timers.js:555:17)
00:14:39 at processTimers (internal/timers.js:498:7){
00:14:39 generatedMessage: true,
00:14:39 code: 'ERR_ASSERTION',
00:14:39 actual: false,
00:14:39 expected: true,
00:14:39 operator: '=='
00:14:39 }
00:14:39 ...

• Build Links: https://ci.nodejs.org/job/node-test-commit-linux-containered/nodes=ubuntu1804_sharedlibs_debug_x64/22684/console

[Trott]

The test seems inherently flaky, likely on all or nearly all platforms. I don't even need to run it concurrently locally to get it to fail. Here's a stress test to see if we can get a handle on how often it fails. https://ci.nodejs.org/job/node-stress-single-test/185/

(EDIT: 1 failure in 856 runs so far on debian9-64. Might be interesting to see if it fails more or less often on slow machines vs. fast machines and if common.platformTimeout() helps. Also might be interesting to experiment with parallel test jobs to see if it is affected by being in parallel or not.)

[Flarna]

One more which has some more info in assert:

AssertionError [ERR_ASSERTION]: 50.29698935913086 <= 50.68267250061035
 at Timeout.r (/home/iojs/build/workspace/node-test-commit-linux/nodes/ubuntu1604-64/test/parallel/test-performance-eventlooputil.js:46:10)
 at Timeout._onTimeout (/home/iojs/build/workspace/node-test-commit-linux/nodes/ubuntu1604-64/test/common/index.js:377:15)
 at listOnTimeout (node:internal/timers:555:17)
 at processTimers (node:internal/timers:498:7){
 generatedMessage: false,
 code: 'ERR_ASSERTION',
 actual: false,
 expected: true,
 operator: '=='
}

https://ci.nodejs.org/job/node-test-commit-linux/37969/nodes=ubuntu1604-64/testReport/junit/(root)/test/parallel_test_performance_eventlooputil/