Cursor becomes ridiculously slow after a few hours of usage

Support Bug Reports
3

Hey, thanks for the report.

This looks like a memory leak or a process issue. Let’s check a few things:

  1. Extension Monitor: Settings > Application > Experimental > enable Extension Monitor, then CMD + Shift + P > Developer: Open Extension Monitor. Which extensions are using the most resources?

  2. Process Explorer: CMD + Shift + P > Developer: Open Process Explorer. Check the extensionHost and ptyHost processes when Cursor starts lagging. How much memory are they using?

  3. Quick test: Try running cursor --disable-extensions from a terminal and use it for a few hours. Does the issue still happen?

  4. MCP servers: Are you using MCP? There’s a similar issue where MCP processes keep piling up: MCP server processes are not terminated and accumulate over time, causing memory leaks

Also, please share:

  • Your codebase size
  • How many agent chats you have open
  • Whether you have a large chat history

This info will help the team narrow down the problem.