vm: kvm_free max_wired

grarpamp grarpamp at gmail.com
Tue Oct 20 02:09:52 UTC 2009

Is this telling me I should be able to set kmem_size to around
740MiB before the kernel panics during boot? Any runtime issues
with doing that?

# sysctl hw.physmem hw.realmem vm.kvm_size vm.kvm_free vm.kmem_size
hw.physmem: 1055293440
hw.realmem: 1072627712
vm.kvm_size: 1073737728
vm.kvm_free: 205516800
vm.kmem_size: 536870912
# sysctl -d hw.physmem vm.kvm_size vm.kvm_free vm.kmem_size
vm.kvm_size: Size of KVM
vm.kvm_free: Amount of KVM free
vm.kmem_size: Size of kernel memory

This doesn't seem to autosize. Is that expected?
Should one care about this sysctl?

vm.max_wired: System-wide limit to wired page count
vm.max_wired: 83211
83211*4096/2^20 = ~325

Also, these are obviously broken / curious:
 debug.boothowto: -2147481598
 net.inet.tcp.inflight.max: 1073725440

Running RELENG_8.

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