Long chats /agent runs completely lag out Cursor agents and terminal commands, etc

[f00z]

This has been an issue since the beginning, and some of it got fixed but now due to longer running agents it’s even worse.

You mention we can leave the agent running for hours, like codex.. i’ve never had it run that long but 30 minutes it has, and I let it run 30 mins, then i come back with another prompt, then it runs again, etc.. but after several times of that it totally lags out, especially with multiple agent tabs open.. it lags so bad the agent shell is minutes behind the chat so it runs into timeouts using the shell (deadline timeout) yet the shell commands eventually run if i let it sit there forever.. it shouldn’t tell the agent the command timed out when it’s ‘queued’ up instead somehow, or maybe it does run but the terminal output is minutes behind.

Switching agent tabs takes a minute during this, even file edits and greps time out.
I’d love to leave the agents running for a long time but it makes the chat HUGE because it’s a lot of it looking at logs and other things which totally lags out the program. Making a new chat session for EVERY prompt is ridiculous and forces agent to re-read tons of things.

What can we do about this?
Also, long chats won’t continue if i reload or restart the program, which is SUPER frustrating.

If i update to new version or reload or restart (all of those restart the window) and try and send a prompt from a long chat, it just sits there forever and eventually times out with a message so it’s impossible to continue that chat. Why doesn’t it save the ‘summarized’ context and just send that so i can continue right where i left off?

[f00z]

I think this may depend on how many commands it executes in the terminal, as it seems like the more it does the laggier it gets and eventually it lags out too much.. could this possibly be related the amount of lines in the terminal scrollback that isn’t being cleared?

[deanrie]

Hey, thanks for the detailed report.

This is a known performance issue during long agent sessions, and the team is aware. Your theory about terminal scrollback could be part of it.

While they’re working on a fix, can you try:

• Clearing the terminal from time to time (Cmd/Ctrl+K or the clear command)
• Not keeping too many agent tabs open at once
• Closing old chats when they get too large

About continuing the chat after a restart, that’s also a known limitation they’re working on.

Can you share your Cursor version and OS? It’ll help with tracking.

[f00z]

Linux OS, Cursor version 2.3.35. But I use Cursor on windows also.

It’s not my terminal, it’s the agent terminal, i can’t run commands on the agent terminal.
It’s 50x worse if i have two chat tabs open with multiple agents using the terminal, so i’m sticking with one right now.
I noticed the terminal because a lot of the times i open the agent terminal in the terminal so i can see it, and i see it going VERY SLOW, like the agent will run a command and the terminal won’t show it for a long time.. so it times out for the agent, but if i just sit there and watch the terminal (even if the agent is stopped) the commands SLOWLY run and show up over many minutes. Even my own terminal is super laggy (if i use the terminal inside cursor to open bash for example)..
I’m using remote-ssh so the terminal is remote-ssh.. Reloading the window or restarting cursor fixes it immediately, but half the time I can’t resume the chat because the length is too large from all the terminal runs the agent did i guess?

[f00z]

On another note, it seems to lag a bit less if i do not open the agent terminal in the external terminal , but i like to see the output which i can’t really see it in the chat window it’s too limited. Maybe it’s just my imagination but it seems to lag faster if i open the external terminal vs not looking at the output and leaving it only in the agent chat window..