questions from FreeBSD user

[Wojciech Puchar <wojtek@xxxxxxxxxxxxxxxxxxxxxxx>]

i have few questions. i am currently using FreeBSD, dragonfly was just 
tried.

1) why on amd64 platform swapcache is said to be limited to 512GB? 
actually it may be real limit on larger setup with more than one SSD.

2) it is said that you are limited to cache about 400000 inodes unless you 
use sysctl setting vfs.hammer.doublebuffer or so.

in the same time it is said to be able to cache any filesystem.

Can UFS be cached efficiently with millions of files?

3) how about reboots? From my understanding reboot, even clean, means 
losing ALL cached data. am i right?


In spite of HAMMER being far far far better implementation of filesystem 
that ZFS, i don't want to use any of them for the same reasons.

UFS is safe.

4) will virtualbox or qemu-kvm or similar tool be ported ever to 
DragonFly? i am not fan of virtualizing everything, which is pure 
marketing nonsense, but i do some virtualize few windows sessions on 
server.

thanks