IIRC dump is special.
As for swap... really, you don't want to swap. If you're swapping you
have problems. Any swap space you have is to help you detect those
problems and correct them before apps start getting ENOMEM. There
*are* exceptions to this, such as Varnish. For Varnish and any other
apps like it I'd dedicate an entire flash drive to it, no ZFS, no
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