Single Claude process consumed 36 GB on 18 GB machine, triggering Jetsam OOM kill (v2.1.37)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report
• [x] I am using the latest version of Claude Code

What's Wrong?

A single Claude Code process (PID 6056) allocated 36.5 GB peak on an 18 GB machine. The system froze completely and required a hard reboot.

This is v2.1.37 — three versions newer than the same leak reported in #24113 (v2.1.34). The problem is getting worse, not better.

The Numbers

Extracted from macOS Jetsam kill logs (JetsamEvent-2026-02-10-113747.ips):

| PID | Version | Current | Peak |
|-----|---------|---------|------|
| 6056 | 2.1.37 | 33,974 MB | 36,484 MB |
| 72799 | 2.1.37 | 3,206 MB | 3,734 MB |
| 42977 | 2.1.34 (zombie) | 1,467 MB | 2,357 MB |
| 46462 | 2.1.37 | 341 MB | 489 MB |
| 29930 | 2.1.37 | 309 MB | 571 MB |
| 4543 | 2.1.37 | 275 MB | 320 MB |
| 21753 | 2.1.37 | 235 MB | 281 MB |
| Total | | 39,808 MB | 44,235 MB |

One process used 2x the total physical RAM. Seven Claude processes combined used 44 GB peak on 18 GB.

Timeline

All times KST (UTC+9), Feb 10 2026:

1. 11:37 — First Jetsam kill. largestProcess: "2.1.37". PID 6056 at 34 GB.
2. 11:52 — Second Jetsam kill, 15 min later. PID 6056 still alive at 36,458 MB — still growing after the first kill.
3. System froze. Hard reboot required.
4. 12:57 — After reboot, macOS caught PID 8457 (new Claude session) writing 2,418 MB in 90 seconds (26.9 MB/s). Footprint grew from 4,750 MB → 9,546 MB in 7 seconds.

Additional Evidence

Disk write diagnostic (2.1.37_2026-02-10-125735_MacBook-Pro-3.diag):

Event:            disk writes
Writes:           2418.41 MB over 90 seconds (26.94 MB/s), exceeding limit of 24.86 KB/s
Footprint:        4749.81 MB -> 9546.31 MB (+4796.50 MB)
Duration Sampled: 7.32s

A new Claude session grew 4.8 GB in 7 seconds after reboot. The leak is immediate, not gradual.

Zombie process: PID 42977 (v2.1.34) was still alive alongside v2.1.37 processes, consuming 1.5 GB. Old versions don't get cleaned up on upgrade.

Comparison with #24113

| | #24113 (Feb 8) | This issue (Feb 10) |
|---|---|---|
| Version | 2.1.34 | 2.1.37 |
| Worst process | 5,810 MB peak | 36,484 MB peak (6.3x worse) |
| Total Claude | 12,740 MB | 44,235 MB (3.5x worse) |
| System state | Swap 96%, still usable | Complete freeze, hard reboot |
| Data source | footprint (live) | Jetsam kill logs (kernel) |

Environment

• Claude Code: 2.1.37 (native macOS app)
• macOS: 26.1 Tahoe (Build 25B78)
• Chip: Apple M3 Pro
• RAM: 18 GB
• Terminal: Ghostty
• Model: Opus 4.6 (1M context)

Steps to Reproduce

1. Use Claude Code native for normal single-user work
2. Machine freezes within hours
3. After hard reboot, check /Library/Logs/DiagnosticReports/JetsamEvent-*.ips
4. largestProcess is Claude

Related Issues

• #24113 — Same reporter, v2.1.34, peak 12.7 GB (this is 3.5x worse)
• #23883 — 13-16 GB in Team mode (Windows)
• #22162 — API client leak (macOS, high-priority)
• #4953 — 120+ GB OOM kill (Linux)