# Cursor Performance after long tasks or writing files

**URL:** <https://forum.cursor.com/t/cursor-performance-after-long-tasks-or-writing-files/154750>\
**Category:** Bug Reports\
**Tags:** performance, chat\
**Created:** [March 14, 2026, 11:55am UTC](https://forum.cursor.com/t/cursor-performance-after-long-tasks-or-writing-files/154750 "2026-03-14T11:55:07Z")\
**Posts on this page:** 1\
**Showing post:** 4

<div class="post-metadata">

**Author:** ![deanrie](https://sea3.discourse-cdn.com/cursor1/user_avatar/forum.cursor.com/deanrie/32/1263_2.png) [@deanrie](https://forum.cursor.com/u/deanrie)\
**Post date:** [March 14, 2026, 12:02pm UTC](https://forum.cursor.com/t/cursor-performance-after-long-tasks-or-writing-files/154750/4 "2026-03-14T12:02:57Z")

</div>

Hey, both issues are known bugs. Quick summary:

1. UI freezes when the agent writes files: we’re seeing this for a few users. It’s related to how the renderer handles file operations.

2. Slowdown in long sessions: you’re right about the root cause. There’s a memory leak in the renderer, so long chats with code blocks keep accumulating memory. Users are seeing the renderer process at 3+ GB, with spikes up to 30 GB.

Related thread with diagnostics: [Cursor UI freezes up when agent is working](https://forum.cursor.com/t/cursor-ui-freezes-up-when-agent-is-working/154197)

For now, the workaround is to periodically close long chats and start new ones. That should reset the renderer’s accumulated memory.

You can also check a couple things for diagnostics:

1. `Ctrl + Shift + P` \> `Developer: Open Process Explorer`: check the memory usage of the “window” process during freezes.
2. `Help` \> `Toggle Developer Tools` \> `Console`: see if there are warnings like `ListenerLeak` or `MaxListenersExceededWarning`.

The team is aware of both issues, and your report helps with prioritization. Let me know if closing chats helps.

---

_[View the full topic](https://forum.cursor.com/t/cursor-performance-after-long-tasks-or-writing-files/154750)._