[bug] Started getting `Too many open files (os error 24)` on `fs:read` after upgrading 1.20.2 -> 1.23.4 on MacOS about moon

[milesj]

@iyefrat Does this happen with all commands or just running a task?

Edit: After looking at the commits, we did fix the auto-clean mechanism. So this may be clean trying to read the metadata of many files? If you run moon clean manually does it error? And if you delete .moon/cache does the error go away?

[iyefrat]

1. it doesn't happen on all commands, or all tasks, just some tasks. it's not entirely deterministic
2. i do get the error when running moon clean, consistently
3. when deleting .moon/cache i can moon check --all to run for a while but it eventually fails on the error, after which other tasks seem to fail more consistently. seems that this error is more likely to happen the more cache files you have.

running du in .moon/cache at this point leads to:

6136	./hashes
(... states subdirectories ...)
7536	./states
8416	./outputs
22104	.

[milesj]

Ok that's helpful, then it definitely seems like the cleaning. Let me rework it a bit so that it doesn't read metadata of these files.

[milesj]

This is actually a bit tricky. I may have to remove this functionality, or wrap it in a setting or something.

Are these large cache files by chance? Or just a ton of small ones?

[milesj]

I've made a few changes that will reduce the amount of syscalls, but not 100% this will fix the problem. I'll pull these into a patch and look into a bigger fix for the next release:

• moonrepo/starbase@2d45ec0
• moonrepo/starbase@ab1b385

[milesj]

Ok I landed those in 1.24, I also added a new setting to control this so you can turn it off if its still an issue.

[iyefrat]

Are these large cache files by chance? Or just a ton of small ones?

I get this with a du . of 11960 and fd . | wc -l of 1050 (on 1.23.4).

Updating to 1.24.1 has fixed the problem. Thanks!