docs(buglog): record Gitea sync for bug-1924

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

2026-10-08 09:38:00 +00:00

3.3 KiB

Raw Blame History

status

status_updated

status_note

component

severity

timestamp

last_seen

occurrences

files

bug-1924: scheduler core clock test fails when the test PID contains 1999 (tlog line includes getpid())

Description

Observed: "scheduler core clock test" failed once in a full scheduler gate run (task 2.2 of scheduler-sim-decision-trace, 2026-10-08), then passed 5/5 on rerun:

../scheduler/testsuite/test_clock.c:351:test_tlog_format_shows_frozen_virtual_time_not_infotime:FAIL: formatted log line must NOT show info->time's wall-clock year while the virtual clock is frozen
15 Tests 1 Failures 0 Ignored

Expected: the test passes on every run. The formatter output is correct; only the assertion is too broad. Impact: noise only. A random, rare failure of the scheduler suite (and of /xce-build scheduler) that has nothing to do with the change under test, costing a rerun and an investigation. No production effect. Found by: spec task scheduler-sim-decision-trace 2.2 (full-suite gate run).

The test sets info->time.year = 1999 and asserts strstr(buff, "1999") == NULL over the WHOLE formatted line. xce_core_tlog_format() (src/scheduler/src/core_clock.c:238-275) prints [%5d] with getpid() in that line, and the frozen virtual time (2033-05-18 03:33:20,000) is constant. So the assertion fails whenever the test process's PID contains the digits "1999" (e.g. 2619991). Confirmed by forcing such a PID (see Reproduction).

Environment

OS: no /etc/os-release; Docker container; NixOS kernel; kernel Linux 6.18.33 x86_64
libc: glibc 2.42-47 (interpreter /nix/store/wb6rhpznjfczwlwx23zmdrrw74bayxw4-glibc-2.42-47/lib/ld-linux-x86-64.so.2)
Toolchain: gcc (GCC) 15.2.0, meson 1.9.1
Build: asan (xce.build)
Code: scheduler-framework @ 54f9139e (first seen on the tree with task 2.2 uncommitted; test_clock.c and core_clock.c unchanged by it)
Deployment: none (unit test binary sched_core_clock_test, meson suite scheduler, test name "scheduler core clock test")

Reproduction

Build: bash src/tools/xce-build.sh scheduler (ASAN, src/xce.build).
sh /home/claude/tmp/bug-1924/repro.sh src/xce.build/scheduler/testsuite burns PIDs until the test binary runs under a PID containing "1999", then prints the result.

Observed 2026-10-08: pid=2612000 PASS; pid=2619991 test_tlog_format_shows_frozen_virtual_time_not_infotime: FAIL (15 Tests 1 Failures).
Frequency: deterministic for a PID containing "1999", otherwise never. Of the PIDs 1..4194304 (this host's pid_max), 2240 contain "1999" (0.053%); in the 2.0M-2.7M range the host was using, 0.034%. The original failure was one such unlucky run.
Evidence: /home/claude/tmp/bug-1924/ (clock-pid1999.out, the forced-PID run; gate22-excerpt.log, the original gate failure; repro.sh).

Root cause

TODO: required for fixed/partial

Fix