Flaky hrtime.phpt test

[mbeccati]

Description

I've never seen this happening, but earlier today I had a number of failures on the ext/standard/tests/hrtime/hrtime.phpt test while doing test runs for the 8.6.0alpha1 packaging.

TEST 1/1 [ext/standard/tests/hrtime/hrtime.phpt]
========DIFF========
001- OK, %f
001+ FAIL, 0.050114826176838
========DONE========
FAIL Test hrtime() aligns with microtime() [ext/standard/tests/hrtime/hrtime.phpt]

Perhaps it could be worth increasing the 0.05 hard limit that is set in the test?

PHP Version

master

Operating System

Ubuntu 26.04

[nicolas-grekas]

Probably not flaky: hrtime() moved to CLOCK_MONOTONIC_RAW in 8.6 (GH-19221) and that clock is not NTP-disciplined, so it drifts with the raw error of the oscillator - 4% here under WSL2, and the test computes 0.038 where 8.5 computes 0.0003.

#23790 moves it back to CLOCK_MONOTONIC, which brings it to 0.0002 here. Could you check whether that makes your Ubuntu 26.04 box happy?

[mbeccati]

@nicolas-grekas Here's the output:

OK, 0.0017711082143941

I don't have however enough knowledge about the change itself and its possible consequences, this specific test aside.