25 seconds is quite not good already though.... it takes a disk a
second or two of no activity to go into low power mode, every 25
seconds means you now have at least a 10% constant power cost....
I don't know the right answer (well other than "make sure inodes aren't
dirty", which involves fixing apps to not do as much file operations,
as well as relatime) but just "every 25s is no big deal" isn't really
the case ;-(
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