How PMAP_SHPGPERPROC relate to vm.v_free_min, vm.v_free_reserved and vm.v_free_target?

[Eduardo Meyer]

Heavy Apache usage is demanding a higher PMAP_SHPGPERPROC kernel
option in my system. However I keep getting the NOTES-documented panic
at boot time, meaning I need to adequately do vm.v_free_min,
vm.v_free_reserved and vm.v_free_target sysctl tuning.

However, this sysctl vars dont have a description and I simply can't
find any further documentation regarding how the vars relate among
themselves and how they related to PMAP_SHPGPERPROC. Can anyone please
explain some basics about how they relate and how I can do the tuning?

It is a 5.5-STABLE with 9GB of memory and PAE enable (sure).

Hackers' feedback or sysadmins' personal experiences are heavily appreciated.

Sorry for cross-posting, I was not sure which list was more adequated.

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Eduardo Meyer
pessoal: dudu.meyer at gmail.com
profissional: ddm.farmaciap at saude.gov.br