The 0.7% is to ensure safe 800kb lower bound on low-end computers.

> Anyway, how about if you try running with the threshold you think we
> should adopt, and report back after a month or so, say?

I am using 250Mb threshold for the last 3 years or so.
GCs are sometimes noticeable, but not annoying:

- gc-elapsed 297 sec / gcs-done 290 -> ~1 sec per GC
- Emacs uptime 2 days 5 hours 21 minutes -> 1 GC per 10 minutes
- memory-limit 6,518,516, stable
  37x from Emacs -Q memory-limit
  10x from Emacs loading with my init.el

-- 
Ihor Radchenko // yantar92,
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