Cursor / Composer / Agent has been much slower for about one week

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

Cursor has been noticeably slower for about one week.

Composer and Agent responses take longer than before. File changes also feel slower, and the overall workflow is less smooth compared to previous weeks.

I use Cursor daily for serious development work, so this slowdown has a real impact on productivity.

Steps to Reproduce

  1. Open Cursor.
  2. Open an existing project.
  3. Start Composer or Agent.
  4. Ask it to analyze files, make changes, or run a normal development task.
  5. The response and file operation speed is noticeably slower than before.

This has been happening consistently for about one week.

Expected Behavior

Composer and Agent should respond and apply file changes with the same speed and smoothness as before.

The development workflow should not become noticeably slower without a clear reason or status update.

Operating System

Windows 10/11

Version Information

Cursor IDE version: I will add the exact version if needed.
Operating system: Windows 11

For AI issues: which model did you use?

Composer / Agent with Claude Sonnet 4 and Auto mode

For AI issues: add Request ID with privacy disabled

I do not have a request ID right now. I can provide one from a slow request if needed.

Additional Information

This does not feel like a single prompt issue. It feels like a general slowdown in Cursor IDE, especially Composer and Agent. The same type of work was faster before.

It happens across normal development tasks such as analyzing project files, editing files, and applying changes.

Does this stop you from using Cursor

Sometimes - I can sometimes use Cursor

Hey, thanks for the report. On the backend side everything looks clean. Your requests are being handled normally, with no errors or timeouts. It looks like the slowdown is on the client side.

To narrow it down, I’ll need a bit of diagnostics:

  1. Exact Cursor version: Help > About or Cursor > About Cursor.
  2. Request ID from a slow request: menu in the top-right of the chat > Copy Request ID. If Privacy Mode is on, please turn it off temporarily for one or two requests.
  3. Check Process Explorer: Cmd+Shift+P > Developer: Open Process Explorer. I’m mainly looking for whether extensionHost or ptyHost is using a lot of CPU or RAM.
  4. Quick sanity check: run Cursor without extensions using cursor --disable-extensions in your terminal. If it’s noticeably faster, it’s likely an extension. You can narrow it down via Extension Monitor: Settings > Application > Experimental > Extension Monitor Enabled.

Also, after long sessions it can help to fully quit and reopen Cursor. Not Reload Window, an actual quit. Agent history and state can build up over time.

Send over the version, the Request ID, and what you see in Process Explorer, and we’ll dig deeper.

Hi, thanks for checking.

Here is the requested information:

Cursor version:
Version: 3.2.11 (user setup)
VSCode Version: 1.105.1
Commit: e9ee1339915a927dfb2df4a836dd9c8337e17cc0
Date: 2026-04-24T14:36:47.933Z
Layout: glass
Build Type: Stable
Release Track: Default
Electron: 39.8.1
Chromium: 142.0.7444.265
Node.js: 22.22.1
V8: 14.2.231.22-electron.0
OS: Windows_NT x64 10.0.26200

Slow Composer request ID:
78b805c2-818a-4ac5-a111-a6c5392637ce

This request felt slow on my side during normal Composer/Agent usage. I will also check Process Explorer and try running Cursor with extensions disabled as suggested.

Cursor version:

Version: 3.2.11 (user setup)
VSCode Version: 1.105.1
Commit: e9ee1339915a927dfb2df4a836dd9c8337e17cc0
Date: 2026-04-24T14:36:47.933Z
Build Type: Stable
OS: Windows_NT x64 10.0.26200

Request ID from a slow Composer request:

78b805c2-818a-4ac5-a111-a6c5392637ce

Process Explorer observations:

CPU usage was not high during the check. Most processes showed 0% CPU.

Memory usage:

  • Shared total: about 3870 MB

  • window [1] (Cursor Agents): about 1032 MB

  • extensionHost: about 319 MB

  • Cursor.exe: about 223 MB

  • fileWatcher: about 127 MB

  • ptyHost: about 148 MB

  • PowerShell: about 86 MB

The biggest visible memory consumer is window [1] (Cursor Agents), around 1 GB. This slowdown happens mainly in Composer/Agent during normal daily development work, especially after longer sessions.

I also opened Workspace Process Explorer.

Current observation:

  • CPU usage is 0% for the visible Cursor processes.

  • Shared memory total is around 3844 MB.

  • Cursor Agents window uses around 1023 MB.

  • extensionHost instances use around 319 MB and 351 MB.

  • gpu-process uses around 339 MB.

  • fileWatcher uses around 127 MB / 115 MB.

  • Several PowerShell / ptyHost processes are open, each around 86 MB, plus conpty-agent processes around 11 MB.

So I do not see high CPU usage, but Cursor Agents is the biggest visible memory consumer, around 1 GB. There are also multiple terminal/ptyHost processes open.

The slowdown is mainly visible in Composer/Agent responses and file operation smoothness during normal development work.

Small update:

I launched Cursor with extensions disabled using:

& “C:\Users\mc_fl\AppData\Local\Programs\cursor\Cursor.exe” --disable-extensions

Cursor shows: “All installed extensions are temporarily disabled.”

With extensions disabled, Composer feels noticeably faster. So the slowdown may be related to an extension or extensionHost on the client side.

My current Cursor version:
Version: 3.2.11 (user setup)
VSCode Version: 1.105.1
OS: Windows 11, Windows_NT x64 10.0.26200

Request ID from a slow Composer request:
78b805c2-818a-4ac5-a111-a6c5392637ce

Process Explorer observations:
Shared memory was around 3.8 GB.
Cursor Agents window used around 1 GB memory.
CPU was mostly 0% when checked.
Several ptyHost / PowerShell / conpty-agent processes were visible.

Hi, I tested Cursor with extensions disabled using --disable-extensions.

It felt noticeably faster with all extensions disabled. After clicking “Reload and Enable Extensions”, I will test again and compare.

My current Cursor version is:

Version: 3.2.11 (user setup)
VSCode Version: 1.105.1
Commit: e9ee1339915a927dfb2df4a836dd9c8337e17cc0
Date: 2026-04-24T14:36:47.933Z
Build Type: Stable
OS: Windows_NT x64 10.0.26200

One slow request ID I copied is:

78b805c2-818a-4ac5-a111-a6c5392637ce

In Process Explorer, I saw around 3.8 GB shared memory usage and the Cursor Agents window around 1 GB memory. CPU was mostly 0% at that moment.

Hi,

I updated Cursor and the Update button is gone now.

Current / previous version I checked:
Version: 3.2.11 (user setup)
VSCode Version: 1.105.1
Commit: e9ee1339915a927dfb2df4a836dd9c8337e17cc0
Date: 2026-04-24T14:36:47.933Z
Build Type: Stable
Electron: 39.8.1
OS: Windows_NT x64 10.0.26200

Request ID from a slow Composer request:
78b805c2-818a-4ac5-a111-a6c5392637ce

I also opened the Workspace Process Explorer. CPU usage was mostly 0%, but memory usage was around 3.8 GB shared. The Cursor Agents window used around 1 GB memory. I also saw several ptyHost / PowerShell / conpty-agent processes.

Then I started Cursor with extensions disabled using:
& “C:\Users\mc_fl\AppData\Local\Programs\cursor\Cursor.exe” --disable-extensions

After that, Cursor felt noticeably faster. So it looks like the slowdown may be related to extensions, long sessions, or accumulated agent/terminal state.

Please let me know what else I should check.

Great job reproducing it with --disable-extensions, that narrowed it down a lot. The backend side looks clean and your Request ID was handled normally, so the slowdown is really client-side and tied to one of the extensions.

To find the specific extension causing it:

  1. Extension Monitor: open Settings > Application > Experimental and turn on Extension Monitor Enabled. Then run Cmd+Shift+P or Ctrl+Shift+P and pick Developer: Open Extension Monitor. You’ll see CPU and memory per extension in real time. Use Composer and Agents for a couple minutes and watch what climbs to the top.
  2. Manual bisect, if the Monitor doesn’t show a clear leader: disable half your extensions, restart Cursor, and test performance. Keep repeating until you find the exact one. Common culprits are heavy language servers like Pylance, Java, C/C++, Tailwind in large projects, or AI extensions that conflict with Cursor.

A couple extra notes from your logs:

  • The Cursor Agents window is around 1 GB, that’s the renderer for the Agents panel. After long sessions, it helps to fully quit Cursor and reopen it, not just Reload Window, since state builds up.
  • You have several ptyHost, PowerShell, and conpty-agent processes. Close unused terminals since they keep memory.

Once you find the extension, reply with which one it is. It’ll help other users and the team see if there’s a pattern.