[Bug] High CPU usage and input lag from futex contention with sched_yield spin-waiting

[blockems]

Bug Description
futex contention + sched_yield spin-waiting causing 80%+ CPU and multi-second input lag

time %	seconds	usecs/call	calls	errors	syscall
67.17	8.648213	1292	6691	593	futex
11.06	1.423371	118614	12	4	restart_syscall
9.77	1.257509	19960	63		epoll_pwait2
7.80	1.004175	85	11791		sched_yield
3.74	0.481445	59	8105		madvise
0.28	0.036002	10	3499		pread64
0.05	0.007019	38	184		statx
0.04	0.005431	27	196	184	access
0.04	0.005192	13	383		clock_gettime
0.02	0.002756	30	89		write
0.01	0.001065	28	38		recvfrom
0.00	0.000453	18	24		timerfd_settime
0.00	0.000342	342	1		gettid
0.00	0.000312	62	5		rt_sigprocmask
0.00	0.000305	12	25	24	epoll_ctl
0.00	0.000244	244	1		clone3
0.00	0.000215	23	9		close
0.00	0.000163	163	1		prctl
0.00	0.000140	17	8		openat
0.00	0.000111	111	1		set_robust_list
0.00	0.000109	109	1		sched_getaffinity
0.00	0.000088	1	55		read
0.00	0.000059	59	1		sched_setscheduler
0.00	0.000029	29	1		rseq
0.00	0.000000	0	1		sendto
100.00	12.874748	412	31185	805	total

Environment Info

• Platform: linux
• Terminal: windows-terminal
• Version: 2.1.4
• Feedback ID: a8e5e4a4-93a2-409b-aa8c-2f0825ce6d04

Errors

[{"error":"Error: String not found in file. Failed to apply edit.\n    at jyH (/$bunfs/root/claude:2039:731)\n    at YC$ (/$bunfs/root/claude:2039:107)\n    at s9D (/$bunfs/root/claude:2092:123)\n    at HdI (/$bunfs/root/claude:1798:2286)\n    at E5 (/$bunfs/root/claude:680:20691)\n    at fG (/$bunfs/root/claude:680:39063)\n    at _R (/$bunfs/root/claude:680:49671)\n    at W5 (/$bunfs/root/claude:680:85807)\n    at ph (/$bunfs/root/claude:680:84787)\n    at Fq (/$bunfs/root/claude:680:84612)","timestamp":"2026-01-11T08:51:02.632Z"},{"error":"Error: String not found in file. Failed to apply edit.\n    at jyH (/$bunfs/root/claude:2039:731)\n    at YC$ (/$bunfs/root/claude:2039:107)\n    at s9D (/$bunfs/root/claude:2092:123)\n    at HdI (/$bunfs/root/claude:1798:2286)\n    at E5 (/$bunfs/root/claude:680:20691)\n    at fG (/$bunfs/root/claude:680:39063)\n    at _R (/$bunfs/root/claude:680:49671)\n    at W5 (/$bunfs/root/claude:680:85807)\n    at ph (/$bunfs/root/claude:680:84787)\n    at Fq (/$bunfs/root/claude:680:84612)","timestamp":"2026-01-11T08:51:03.896Z"},{"error":"Error: String not found in file. Failed to apply edit.\n    at jyH (/$bunfs/root/claude:2039:731)\n    at YC$ (/$bunfs/root/claude:2039:107)\n    at s9D (/$bunfs/root/claude:2092:123)\n    at HdI (/$bunfs/root/claude:1798:2286)\n    at E5 (/$bunfs/root/claude:680:20691)\n    at fG (/$bunfs/root/claude:680:39063)\n    at _R (/$bunfs/root/claude:680:49671)\n    at W5 (/$bunfs/root/claude:680:85807)\n    at ph (/$bunfs/root/claude:680:84787)\n    at Fq (/$bunfs/root/claude:680:84612)","timestamp":"2026-01-11T08:51:13.437Z"},{"error":"Error: String not found in file. Failed to apply edit.\n    at jyH (/$bunfs/root/claude:2039:731)\n    at YC$ (/$bunfs/root/claude:2039:107)\n    at s9D (/$bunfs/root/claude:2092:123)\n    at HdI (/$bunfs/root/claude:1798:2286)\n    at E5 (

Note: Error logs were truncated.

[github-actions]

Found 2 possible duplicate issues:

1. High CPU usage (27-33%) when idle - busy-wait loop in sched_yield/futex #17142
2. [BUG] Critical performance regression on WSL2: Slash commands trigger infinite futex spinlock causing 110% CPU usage (v2.0.76 & v2.0.67) #15689

This issue will be automatically closed as a duplicate in 3 days.

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[github-actions]

This issue has been automatically closed as a duplicate of #17142.

If this is incorrect, please re-open this issue or create a new one.

🤖 Generated with Claude Code

[github-actions]

This issue has been automatically locked since it was closed and has not had any activity for 7 days. If you're experiencing a similar issue, please file a new issue and reference this one if it's relevant.