test(code-runtime-python): correct the dual-limit CPU overrun assertion and use a hard limit >= 2

The dual-limit CPU test used ulimit -t 1 (hard == 1), which the _clamped
soft-lowering guard (hard >= 2) intentionally does not lower, and trapped
SIGXCPU (which defeats the fix). Use ulimit -t 2 (hard == 2, so the soft is
lowered to 1) and leave SIGXCPU unhandled; the run then classifies as a timeout.
The message is the CPU-time-exhausted diagnostic, not the literal 'SIGXCPU'.
This commit is contained in:
Chinesezjc
2026-08-31 14:33:31 +08:00
committed by Tianyi Cui
parent dcbce50ec2
commit 72241b9f06
@@ -513,25 +513,22 @@ describe('PythonCodeRuntime — inherited resource limits', () => {
it('reports a CPU overrun under a dual-limit ulimit as a timeout, not a worker-exit', async () => {
// `ulimit -t N` sets BOTH the soft and hard CPU limit to N. The kernel
// checks the hard limit in the same tick and SIGKILLs a busy loop directly,
// so SIGXCPU is never delivered — and the host classifies a CPU overrun
// ONLY on `signal === 'SIGXCPU'`, so the overrun would be misreported as a
// `worker-exit` instead of a timeout. `_clamped` now lowers a clamped
// soft==hard result by one unit (when hard >= 2), so SIGXCPU fires at the
// softer limit and the run reports a timeout. This drives a busy loop past
// the inherited cap and asserts the run classifies as a timeout.
// checks the hard limit and SIGKILLs a busy loop directly, so with
// soft == hard the SIGXCPU signal is never delivered — and the host
// classifies a CPU overrun ONLY on `signal === 'SIGXCPU'`, so the overrun
// would be misreported as a `worker-exit` instead of a timeout. `_clamped`
// now lowers a clamped soft==hard result by one unit (when hard >= 2), so
// the SIGXCPU signal fires at the softer limit and the run reports a
// timeout. This uses `ulimit -t 2` (hard == 2, so the soft is lowered to 1)
// and leaves SIGXCPU unhandled, so the kernel terminates the busy loop at
// 1 s with SIGXCPU and the host classifies it as a timeout.
const dir = await mkdtemp(join(tmpdir(), 'dsh-rlimit-dual-'))
const wrapper = join(dir, 'python3-dual-capped')
// Both soft and hard CPU 1 s; configured cpuSeconds 30 s.
await writeFile(wrapper, '#!/bin/sh\nulimit -t 1\nexec python3 "$@"\n', { mode: 0o755 })
// Both soft and hard CPU 2 s; configured cpuSeconds 30 s.
await writeFile(wrapper, '#!/bin/sh\nulimit -t 2\nexec python3 "$@"\n', { mode: 0o755 })
const { runtime } = await setup({ pythonBin: wrapper, cpuSeconds: 30, maxWallMs: 12_000 })
const result = await runtime.run({
program: [
'import signal',
// Trap SIGXCPU; with the soft limit one unit below the hard it fires at
// 1 s and the run is classified as a CPU timeout, not a worker-exit.
'signal.signal(signal.SIGXCPU, lambda *a: None)',
'end = 2.5',
'while True:',
' pass',
'return "unreachable"',
@@ -539,7 +536,7 @@ describe('PythonCodeRuntime — inherited resource limits', () => {
bindings: [],
})
expect(result.error?.kind).toBe('timeout')
expect(result.error?.message).toContain('SIGXCPU')
expect(result.error?.message).toContain('CPU time exhausted')
}, 15_000)
it('rechecks CPU at settlement against the effective inherited soft limit', async () => {