Renderer command line (js-flags NOT passed to renderer)
--max-old-space-size=65536 set in argv.json does NOT appear in renderer process
command line. The flag only affects the main process, not the renderer.
Process snapshot at time of investigation
ProcessId WorkingSet_MB Type
71536 5146 renderer ← this one crashes
62916 625 renderer
60664 445 gpu-process
71176 260 main
What I already tried (none helped)
✗ argv.json: "js-flags": "--max-old-space-size=65536" — does not affect renderer
✗ argv.json: "disable-hardware-acceleration": true — crash still happens
✗ --disable-extensions — crash still happens (Agent is built-in)
✗ Cleared CachedData, GPUCache, Cache directories
✗ settings.json: "window.restoreWindows": "none"
✗ Created .cursorignore excluding build dirs (project only has 36 files)
✗ Increased page file from 8 GB to 32 GB
✗ Extended files.watcherExclude
Key observations
Crash is Windows-specific — same machine on Ubuntu works fine
Crash happens in renderer process, not main or extension host
js-flags from argv.json do NOT propagate to renderer processes
Indexing completes in 3 seconds (36 files) — not the cause
128 GB RAM with 76+ GB free — not a system memory issue
The leaking renderer is always the one running Agent chat
Multiple windows (3-4) accelerate the issue but single window also crashes
Expected behavior
Renderer process should not grow unbounded. Either implement memory limits for
renderer processes or fix the memory leak in the Agent chat rendering pipeline.
Steps to Reproduce
Fresh install Cursor 2.5.20 on Windows 11 (128 GB RAM, RTX 5080)
Open any project (even small — 36 files Android/Gradle project)
Open Agent chat (Ctrl+L or Cmd+L)
Send 3-5 messages in Agent mode
Wait ~3 minutes
Renderer process grows from 600 MB → 3 GB → 5 GB → crash
Dialog appears: “The window terminated unexpectedly (reason: ‘oom’, code: ‘-536870904’)”
Click “Reopen” — crash repeats in ~3 minutes again (crash loop)
Note: Does NOT reproduce on Ubuntu (same hardware, dual-boot). Windows-only.
Same here! I completely rebuilt my entire machine and everything worked fine for about 24 hours and now the problem is back. I am on a Windows 11 machine with 64GB of RAM using WSL with Ubuntu. I’ve been using this configuration for nearly a year with no problems. THIS IS A CURSOR BUG!!! Please resolve it asap!!
Same problem here! Since 4 days is my cursor not usable anymore. I have to reopen all 2-3 minutes, even though I have enough RAM available. Always the same error message. Even after a re-install: 24h later, I got exactly the same issue. Please resolv it as soon as possible.
Same problem here for the past 2-3 days..
it’s really annoying because very often it lsoes what just got edited, making rollback complicated, knowing which files got edited or not and AI endeding up with an imcompleted task..
sometime it even crashes AFTER a prompt and editing was completed.. and yet when restarting, the last message and recap from the prompt is gone anyway.. sometime it even crashes while I’m literally halfway reading the AI’s recap I hope this gets fixed soon.
Can you please provide the exact version of Cursor that you’re using, alongside system details (Help > About or Cursor > About Cursor depending on your system).
Hi @Colin this is likely happening due to agent transcript writes (.jsonl), when serializing the json transcript Cursor goes above 4gb in usage and crashes as a result. Tool calls such as subagents also make the OOM happen faster.
This means I often have to start a new chat instead and abandon an old one, once a specific chat causes this. This is also the reason why it keeps repeating for some users, because they’re using an old chat that causes the issue.
We have fixed quite a few memory issues in 2.6, so please try upgrading (you can pull from https://cursor.com/downloads if your cilent hasn’t auto-updated)!
After updating to 2.6.11, I noticed right away that the program was running awfully slow, after a couple of prompts and basic operations RAM usage skyrocketed to 5GB+ (and climbing lol) with CPU usage hovering around 20-30% which points to some sort of memory leak.
Killing the process via task manager and a fresh restart to the welcome window “fixes the issue”, HOWEVER reopening the workspace (that has git history and a couple of active chats with agents) starts leaking memory again, the leak is so severe I can barely get to the built in process explorer without cursor crashing.
I now have the out of memory issue. I didn’t have an issue until cursor updated to 26.11 yesterday. My main project I can no longer work on because cursor closes within a couple of minutes. My backup dev machine has updated itself to the same version and is doing exactly the same thing.
Cursor is very unresponsive now on my other projects when I look at an existing agent chat.
Both pcs, 64gb memory, running nothing else.
I’d like to install the previous build, but the last previous I can see is 2.5
I hope this gets fixed soon.
