Wezterm getting memory allocation failure if configured with large scrollback_lines buffer

[chhetripradeep]

What Operating System(s) are you seeing this problem on?

macOS

Which Wayland compositor or X11 Window manager(s) are you using?

No response

WezTerm version

20240203-110809-5046fc22

I have tested with latest nightly build too. Noticing the same behaviour too.

Did you try the latest nightly build to see if the issue is better (or worse!) than your current version?

Yes, and I updated the version box above to show the version of the nightly that I tried

Describe the bug

I have a config in my wezterm.lua

config.scrollback_lines = 100000000000

It seems like wezterm allocates the total memory of the configured number of lines as soon as the new tab is opened. Ideally it should do incremental memory allocation. Thus after opening certain number of tables, wezterm gets oom-killed.

❯ wezterm
memory allocation of 13600000008568 bytes failed

To Reproduce

Add the config to wezterm.lua

config.scrollback_lines = 100000000000

And open tabs. It should get oom-killed.

Configuration

config.scrollback_lines = 100000000000

Expected Behavior

Wezterm shouldn't preallocate the memory required for all the scrollback_lines ahead of time with the expectation that all will be used. It shouldn't get oom-killed in such scenarios.

Logs

❯ wezterm memory allocation of 13600000008568 bytes failed

Anything else?

No response