[arch-general] Extremely slow battery status on MBP

[Emanuel Evans]

Apologies for the repeat posting--I think my previous posting ended up
bouncing due to some misconfigured dmarc settings. Anyways, I have kind
of a weird issue that I'm having trouble debugging. On my MacBook Pro
(11,1), checking battery status (through acpi or the /sys filesystem)
becomes extremely slow after the computer's been on for a while. Here's
an example:

$ time cat /sys/class/power_supply/BAT0/status
Charging

real	0m54.519s
user	0m0.000s
sys	0m4.663s

dmesg and journalctl aren't outputting anything during the call, and I
tried strace during the command and there was no output during the
blocked time. It's highly intermittent--acpi can take anywhere from 0-60
seconds with no discernible pattern, except that it doesn't happen when
the battery is plugged in and charged. Any ideas for how to debug this
further, or possible solutions? Thanks so much!