runtime:cpu1: TestPreemptionAfterSyscall/10µs failures

Description

#!watchflakes
default <- pkg == "runtime:cpu1" && test == "TestPreemptionAfterSyscall/10µs"

=== RUN   TestPreemptionAfterSyscall/10µs
    proc_test.go:1082: timeout exceeded: 5.598432875s (5s)
--- FAIL: TestPreemptionAfterSyscall/10µs (6.57s)

Contributor guide

Tech stack

go

Domain

backendtesting

Issue type

bug

DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.

5

Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.

over 1 week

Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.

active

ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.

mostly clear

Prerequisites

Go programming languageunderstanding of Go runtime schedulerfamiliarity with syscall handling

Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.

10

Research direction

Reproduce the flaky test failure by running TestPreemptionAfterSyscall/10µs under stress. Investigate the Go runtime scheduler's preemption logic, especially related to syscall handling in runtime/proc test.go and runtime/syscall linux.go. Check recent commits that may have introduced the timeout regression. The issue has 116 comments; review them for potential root causes and proposed fixes.