Screen lag/freezing when typing text (WSL2, TMUX, Alacritty)

[matevszm]

Description

I have recently started using opencode and I think it's a great tool, but unfortunately, when writing prompts, I experience unpleasant freeze/lags for few seconds. I use opencode inside WSL 2 on Windows 11, using the alacritty terminal inside tmux, although I checked and tmux has nothing to do with it here, I use bash.

I did not observe anything like that during the work of agent itself.

The GIF shows an unpleasant lag that disturbs with writing longer prompts and is simply annoying. Has anyone experienced something similar or knows how to fix it?

Ubuntu 24.04.2 LTS
Opencode 1.1.20
alacritty 0.16.1 (42f49ee)
WSL version: 2.6.3.0
Linux kernel: 6.6.87.2-1

Steps to reproduce

Run alacritty terminal on windows with WSL2 (ubuntu) inside, run opencode and start type

[github-actions]

This issue might be a duplicate of an existing issue. Please check:

• Severe scroll lag in VSCode/Cursor integrated terminal on WSL2 after large output (unusable for minutes) #7893: Severe scroll lag in VSCode/Cursor integrated terminal on WSL2 after large output (unusable for minutes) - While this mentions scroll specifically, it documents WSL2 terminal performance issues similar to your typing lag experience, likely related to the same underlying TUI rendering problem on WSL2.

Feel free to ignore if your issue is specific to input/typing lag rather than general scrolling/rendering lag.

[xxzefgh]

Same for me, WSL2, Wezterm/Windows Terminal. It also started happening sometime after 1.0 release. My freezes are actually 10 seconds or more, completely unusable. Works on a different machine with the same setup 🤷‍♂️

[pattonjh]

This is happening to me as of yesterday as well. It's immensely frustrating. It also applies to scrolling through the opencode window, not just typing. I am also using Ubuntu via WSL.

[Tylopilus]

Can confirm. I have the same issue displayed in the video

[shahabsalehi]

I’ve run into this issue multiple times on WSL2. These are the fixes that consistently worked for me.

1. Cleaning up the disk, making sure that there is free space available

2. Ensure system time is correctly synced
   If your Windows system clock is out of sync (for example, 1 hour ahead due to DST or time sync issues), opencode can appear to freeze.
   Internally, opencode uses time-based waits (e.g. CLOCK_REALTIME). When the system clock jumps or is incorrect, these waits can behave incorrectly and cause the UI to stop.

If none of the above worked, try to see the logs with strace:

sudo apt install -y strace
Run opencode until it freezes
Open a new terminal

Find the PID: pgrep -n opencode

Attach strace: sudo strace -p -f -s 200

If you see repeated futex(...) and sched_yield() calls (especially with FUTEX_CLOCK_REALTIME), it’s likely a time-sync or event-loop issue.

If you see other problems I guess gpt could help.

[pschiel]

These lags occur when you have systemd-timesyncd enabled.

What happens is that WSL will adjust the time differently than Windows, and Hyper-V correcting time back into the past - which causes corrupt timestamps, freezes in the client, as Javascript timeouts will suddenly wait seconds.

Try sudo systemctl disable systemd-timesyncd && sudo systemctl stop systemd-timesyncd

[caozhiyuan]

try disable animations and set env set OPENCODE_DISABLE_TERMINAL_TITLE=1 #8667 (comment) @matevszm

[IPPO181]

These lags occur when you have systemd-timesyncd enabled.

What happens is that WSL will adjust the time differently than Windows, and Hyper-V correcting time back into the past - which causes corrupt timestamps, freezes in the client, as Javascript timeouts will suddenly wait seconds.

Try sudo systemctl disable systemd-timesyncd && sudo systemctl stop systemd-timesyncd

Thank you, this fixed my issue.