Rhombus memory usage grows when terminal window closed

[eleftasia]

When I open a Rhombus REPL from the terminal and then close the terminal window without first killing the Rhombus REPL, the Racket process running the Rhombus REPL continuously grows to use more and more memory. This happens without the Rhombus REPL running any code (the process was running in a now-closed terminal window) and without DrRacket being open.

Machine: 2021 MacBook Pro 16-inch
Chip: Apple M1 Pro
Memory: 16 GB
OS: macOS Sonoma 14.5
Racket version: v8.14.0.2-2024-07-31-f82a96e5a9

Steps taken:

1. Open a new terminal window
2. racket -l rhombus -i
3. Wait until > appears on a new line showing the REPL is ready to use
4. Close the terminal window

Screenshots:

• Taken at 14:28

• Taken at 14:42 (14 minutes later)

• Taken at 14:48 (6 more minutes later)

[sorawee]

Wondering if it's related to racket/racket#4964. Is the CPU usage also high?

[eleftasia]

I just walked through the steps I listed again and activity monitor is reporting high CPU usage also. (I tried to attach an image but GitHub didn't like that so I'll just say that it peaked at ~98% CPU usage but dropped down since then.)

[eleftasia]

I sampled the process using Activity Monitor and this is what I got:

https://gist.github.com/ellifteria/9cb9b50a371a3c75a953136cf16249a7

It looks like most of the call stack is the GC.

[mflatt]

Are your terminal and shell the usual "Terminal.app" and "zsh"?

Assuming "Teminal.app", when you close the terminal window, does it ask about terminating processes?

Just to make sure, the -l rhombus part is needed, and you don't see this behavior with just racket, right?

[robertDurst]

Was curious so I tried this out - not sure how to close terminal window without terminating the program, but even just booting rhombus as racket -l rhombus -i here and comparing to just racket, I see the CPU spike:

Untitled.mov

Unfortunately @eleftasia's sampling link wasn't working for me. Suppose GC might make sense. I am super new to Racket and Rhombus as a contributor (and hence skimming issues looking for places to get involved 😄), but imagine there's some startup cost? I know at least for typed-racket, I was experiencing startup-cost for #lang typed/racket which was slower than #lang typed/racket/base... which was slower than #lang racket... vs. #lang racket/base.

Also during the day I work on production software (Ruby) and we shake our fist at the startup cost we've grown to there.

---

Some Info on Versions and Such

My machine:

Racket/Rhombus:
And I am on racket 8.17 with a fresh install of rhombus via raco, so the latest and greatest on master as of writing.

Terminal:
Mac default, running zsh shell.

---

This Issue is over a year old at this point. Is this an interesting exploration or not worth the time? @mflatt