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

[Piesson]

Preflight Checklist

• I have searched existing issues and this hasn't been reported yet
• This is a single bug report
• 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

• Memory spike: 3 processes peaked at 12.7 GB combined on 18 GB machine (v2.1.34, macOS native) #24113 — Same reporter, v2.1.34, peak 12.7 GB (this is 3.5x worse)
• [BUG] High memory usage (~13-16 GB) when using Team/Teammate mode #23883 — 13-16 GB in Team mode (Windows)
• [BUG] Memory leak: API clients created repeatedly instead of reused (8-9 GB memory usage) #22162 — API client leak (macOS, high-priority)
• Claude Code Memory Leak - Process Grows to 120+ GB RAM and Gets OOM Killed #4953 — 120+ GB OOM kill (Linux)

[github-actions]

Found 3 possible duplicate issues:

1. Memory spike: 3 processes peaked at 12.7 GB combined on 18 GB machine (v2.1.34, macOS native) #24113
2. [BUG] Critical macOS 26.2 Memory Leak — Claude Desktop Background Processes #23496
3. Bug: Claude Code 2.1.32 regression - allocates ~11GB RAM on launch, freezes terminal (2.1.30 works fine) #23442

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

• If your issue is a duplicate, please close it and 👍 the existing issue instead
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🤖 Generated with Claude Code

[Piesson]

This is not a duplicate.

• Memory spike: 3 processes peaked at 12.7 GB combined on 18 GB machine (v2.1.34, macOS native) #24113: v2.1.34, peak 12.7 GB total — system was still usable
• Single Claude process consumed 36 GB on 18 GB machine, triggering Jetsam OOM kill (v2.1.37) #24583 (this): v2.1.37, peak 44.2 GB total, single process hit 36.5 GB — complete system freeze, hard reboot required

Same machine, same user, 3 versions later, 3.5x worse. This is a regression, not a repeat.

This issue makes Claude Code practically unusable. My machine freezes every few hours and I lose all unsaved work. It needs urgent attention.

[SalilMonga]

I upgraded after a while and noticed that my macbook started overheating even during normal use. Saw this issue and I am on v2.1.37 on an M4 Pro Macbook pro. Claude was idle for about 1 hour and even then the memory use was over 22 gigs.

Edit: I tested it again on v2.1.38, restarted everything: the memory was hovering around 1.9 gigs for a while and then suddenly it jumped to 22 gigs within 30 seconds

[Piesson]

Same here. Switched from npm to native and my M3 Pro MacBook Pro has been burning up ever since. On v2.1.37, Claude was just sitting slow for about an hour and memory ballooned to 22GB.

Honestly just wanna go back to the npm version at this point lol

[SalilMonga]

I have been using native claude cli since day 1, and I noticed that you did open another issue with the memory leak for native app and causing your MacBook to shut down? I am assuming that this issue is for the npm claude code setup? @Piesson
Update: Today I haven't had any memory leaks that were noticeable at all. So far around 8 hours in of using it and it's not even in the top 10 tasks of using my memory. I did not update or make any changes since my yesterday's update

[Piesson]

Both issues are about the bun-based native version of Claude Code. #24960 is just the latest one where it escalated to a kernel panic. Have you not experienced any memory spikes since switching to native?