Remote SSH extension host crashes + forkpty failed on Minerva HPC (resource limit issue persists after update)

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Hey, thanks for the new thread with all the diagnostics. That really helps.

From the logs and ulimit -a, the cause is pretty clear. The main issue is max user processes (-u) 256. That’s critically low for Cursor Remote SSH. The Cursor server on the remote machine starts 10+ processes like server-main, fileWatcher, ptyHost, extensionHost, git, bash, and so on. With a limit of 256, the system just refuses to create new processes.

The logs back this up:

  • Lots of Error: spawn /usr/bin/git EAGAIN which means the OS can’t fork a new process for git
  • Error: spawn /bin/bash EAGAIN same for bash and the terminal, which is why you see forkpty failed
  • WebAssembly.instantiate(): Out of memory likely related to the virtual memory (-v) 40971520 40GB limit, so WebAssembly modules can’t allocate memory

So the extension host crashes, restarts, hits the limit again, and loops like that.

What you need to do:

Ask the Minerva HPC admins to increase max user processes for your account. Ideally set it to 4096 or higher. This is usually configured via /etc/security/limits.conf or via SLURM or LSF policies.

If you can add this yourself in ~/.bashrc:

ulimit -u 4096

It’ll only work if the hard limit allows it, so check ulimit -Hu.

Also, if you can run on a compute node instead of a login node, li04e04 looks like a login node, compute nodes usually have higher limits.

This isn’t a Cursor bug. It’s an HPC environment limit. Cursor just needs more than 256 processes to work properly over Remote SSH.

Let me know if you’re able to raise the limit.