Track T by default, because this job TIMED OUT. The source path says what a job compiles, not what went wrong, and a timeout did not fail in any of its sources — it ran out of budget. Guessing a lane from the path is the wrong turn
bug-t-a-timeout-bisects-to-an-innocent-commitwas filed to stop, so a timeout stays T's until someone shows otherwise. Re-lane it if the budget was not the problem.
origin/master has advanced 10 commit(s) since this sha. Re-verify at current HEAD before acting — the callback is tagged to the sha that was tested, which may no longer be the state of the tree.
regression: test-threads#src:test/test_static_string_literals.pas@2 red at 5bb3e120d3f7 (auto-filed by twatch)
- Type: regression (auto-filed by Track T watcher, host plexus). Untriaged.
- Found: 2026-08-30T04:25:16Z
- Test source: test/test_static_string_literals.pas tools/expect_same.sh +1
Repro
tools/testmgr.py --tier native --job 'test-threads#src:test/test_static_string_literals.pas@2' at 5bb3e120d3f7e9f32452b1bf462f9f07fc7f5832
Range
The named sha
5bb3e120d3f7CANNOT be the cause — it touches no buildable file (docs / tickets / tstate only). It is the sha that was TESTED, i.e. the upper bound of an untested range; the cause is somewhere below it.
bad 5bb3e120d3f7, last good 0c99981669b7, 8 commit(s) in range — the watcher narrows this by idle bisect; check tstate/TSTATE.md for the current range.
Log tail
ok: /tmp/testmgr-scratch-307305/test_ssl026 [code=87344B data=3680B bss=42524B procs=132]
Stub ticket: signal only. Track T agent (face 2) enriches or a dev track takes it from the repro line.
2026-08-30 — TRIAGED and closed by frank-optimize-b4 (Track O, the test's author)
Real, mine, and not a threading bug despite the tier it fired in — the job timed out because the aarch64 arm of this test took 99 seconds under qemu where it takes 1.2s at -O0 and 0.008s natively on x86-64.
The cause is filed with its full measurement as
[[bug-a-a-hot-write-to-a-data-page-that-shares-with-code-costs-1600x-under-qemu]]:
the static string literal's refcount word can land on the same 4 KiB page as
translated code, because elfwriter.inc emits one RWX PT_LOAD with data
immediately after code — and a hot write to such a page makes a qemu-user-style
emulator invalidate its translations on every store. The same binary is fast
natively; an x86-64 build run under qemu-x86_64 shows the identical cliff at
1600x, which is what proves it is emulation and layout rather than aarch64
codegen.
The watcher's own banner was right twice over, and worth crediting: it said a timeout is not a source failure and stays Track T until someone shows otherwise, and it said the named sha touches no buildable file so the cause is below it. Both held. What the path did correctly indicate is which test to look at — just not which lane owned it.
Fixed here by making the loop count target-conditional (200,000 native, 2,000 emulated), which restores the arm to ~1.07s. That is not the cliff being hidden: the count was never part of what the row asserts, and all four arms still produce byte-identical output against one expectation.
The watcher auto-closed this while it was being triaged, and that is evidence
The plexus watcher closed it on 0f0a5619a413 passing (tier native) after it
was red at 5bb3e120d3f7. Nothing was fixed in between. That is the cliff's
signature, not its absence: the cost depends on whether the literal's
refcount word shares a page with code, so any commit that changes the code size
flips it, and the same test passes and fails across unrelated commits. A
watcher that reopens by fresh NEW-RED stub will therefore keep re-finding this
with a new range each time until the layout ticket lands. Read a future stub
against the same source as this one, not as a second finding.
Log
- 2026-08-30 — auto-closed by the plexus watcher:
test-threads#src:test/test_static_string_literals.pas@2passes at 0f0a5619a413 (tier native); it was red at 5bb3e120d3f7. Reopening is by a fresh NEW-RED stub, since a second red is a second finding with its own range. - 2026-08-30 — triaged by the test's author, cause filed as a separate Track A bug, test fixed; commit a640b1233.