test_eintr: test_flock() fails with: 0.19043820584192872 not greater than or equal to 0.2

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Failure on AMD64 RHEL8 3.x buildbot:

FAIL: test_flock (__main__.FNTLEINTRTest.test_flock)
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Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.x.cstratak-RHEL8-x86_64/build/Lib/test/_test_eintr.py", line 526, in test_flock
    self._lock(fcntl.flock, "flock")
  File "/home/buildbot/buildarea/3.x.cstratak-RHEL8-x86_64/build/Lib/test/_test_eintr.py", line 515, in _lock
    self.assertGreaterEqual(dt, self.sleep_time)
AssertionError: 0.19043820584192872 not greater than or equal to 0.2

build: https://buildbot.python.org/all/#/builders/185/builds/5045

dt is measured with time.monotonic(). test.pythoninfo says:

time.get_clock_info(monotonic): namespace(implementation='clock_gettime(CLOCK_MONOTONIC)', monotonic=True, adjustable=False, resolution=1e-09)

sleep_time = 0.2 constant is used to call time.sleep(0.2) in a child process which is created after start_time = time.monotonic().

Linked PRs

• gh-109592: test_eintr tolerates 20 ms when comparing timings #110102
• [3.12] gh-109592: test_eintr tolerates 20 ms when comparing timings (GH-110102) #110106
• [3.11] gh-109592: test_eintr tolerates 20 ms when comparing timings (GH-110102) #110107

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time.sleep() is implemented with clock_nanosleep() on this buildbot. configure says:

checking for clock_nanosleep... yes