我找到了这个片段：

config.vm.provider "virtualBox" do |v|
      host = RbConfig::CONFIG['host_os']
      # Give VM 1/4 system memory & access to all cpu cores on the host
      if host =~ /darwin/
        cpus = `sysctl -n hw.ncpu`.to_i
        # sysctl returns Bytes and we need to convert to MB
        mem = `sysctl -n hw.memsize`.to_i / 1024 / 1024 / 4
      elsif host =~ /linux/
        cpus = `nproc`.to_i
        # meminfo shows KB and we need to convert to MB
        mem = `grep 'MemTotal' /proc/meminfo | sed -e 's/MemTotal://' -e 's/ kB//'`.to_i / 1024 / 4
      else # sorry Windows folks,I can't help you
        cpus = 2
        mem = 1024
      end

      v.customize ["modifyvm",:id,"--memory",mem]
      v.customize ["modifyvm","--cpus",cpus]
end

但是它没有Windows(它设置默认值2和1024).

任何人都有任何线索如何做到这一点？