Screen rendering locks up under extreme stdout/stderr load

Discord username (optional)

aremmell

Describe the bug

I develop a library that among other things, does formatted logging to stdout/stderr. My test rig has a --perf flag, which causes it to log millions of lines as fast as possible while keeping track of elapsed time.

Warp is the first emulator that I have encountered (and I have tested them all) that will not show any of the output until all of the lines have been written (I see a beach ball and no output for 5-6 seconds), then some output will start to appear once things slow down. The history is there–if I scroll up, my data is in the backlog, but it just doesn't scroll by on the screen while it's actively writing to the console.

To reproduce

If you would like to repro for yourself (I will be surprised if this is the first report you're getting of this nature):

1. git clone https://github.com/aremmell/libsir.git
2. cd libsir && make tests && build/bin/sirtests --perf

Expected behavior

stdout output immediately begins scrolling by (very quickly)

Screenshots

It is running in this screenshot; the beach ball isn't visible, but it would be if I could move the mouse and take a screenshot at the same time:

Operating system

MacOS

Operating system and version

13.5.1

Shell Version

zsh 5.9 (x86_64-apple-darwin22.0)

Current Warp version

v0.2023.08.29.08.04.stable_00

Regression

No, this bug or issue has existed throughout my experience using Warp

Recent working Warp date

n/a

Additional context

No response

Does this block you from using Warp daily?

No

Is this a Warp specific issue? (i.e. does it happen in Terminal, iTerm, Kitty, etc.)

Yes, this I confirmed this only happens in Warp, not other terminals.

Warp Internal (ignore): linear-label:b8107fdf-ba31-488d-b103-d271c89cac3e

None

Start by running the reported reproduction, build/bin/sirtests --perf, after building libsir with make tests, and observe Warp's terminal output while stdout/stderr are saturated. Trace the terminal output and screen-rendering entry points; done means output begins scrolling promptly without locking up, while retaining the full history.