启动 ubuntu 16.04 需要 20-25 秒，可能没那么多，但比 15.04 长 2 倍。问题可能出在 apparmor 上。有什么建议我可以怎么做吗？
systemd-analyze 责任：
11.858s apparmor.service
5.931s NetworkManager-wait-online.service
1.444s systemd-fsck@dev-disk-by\x2duuid-f1d80aeb\x2d9dc2\x2d4916\x2dab84\x2d840f434f295f.service
1.049s systemd-fsck@dev-disk-by\x2duuid-074fa7fd\x2d15b5\x2d480b\x2d9247\x2ddd4cfa3f3325.service
896ms systemd-fsck@dev-disk-by\x2duuid-b844937e\x2d560e\x2d4946\x2dbea0\x2d69a69c57b822.service
608ms systemd-fsck@dev-disk-by\x2duuid-dc0d52c7\x2d9c0f\x2d4962\x2dbc4b\x2dec0329a69bd9.service
498ms systemd-fsck@dev-disk-by\x2duuid-ae6ec5bf\x2d9c14\x2d4115\x2d89b0\x2d5e73e6871133.service
.......
dmesg：
4.279696] EXT4-fs (sdb2): mounted filesystem with ordered data mode. Opts: (null)
[ 4.673766] EXT4-fs (sdb1): mounted filesystem with ordered data mode. Opts: (null)
[ 4.700503] systemdenter code here-journald[268]: Received request to flush runtime journal from PID 1
[ 5.622772] EXT4-fs (sdb4): mounted filesystem with ordered data mode. Opts: (null)
[ 5.936253] EXT4-fs (sdb7): mounted filesystem with ordered data mode. Opts: (null)
[ 5.991500] EXT4-fs (sdb6): mounted filesystem with ordered data mode. Opts: (null)
[ 17.836097] audit: type=1400 audit(1463414821.669:2): apparmor="STATUS" operation="profile_load" profile="unconfined" name="/usr/bin/ubuntu-core-launcher" pid=828 comm="apparmor_parser"
[ 17.839280] audit: type=1400 audit(1463414821.673:3): apparmor="STATUS" operation="profile_load" profile="unconfined" name="/sbin/dhclient" pid=825 comm="apparmor_parser"
[ 17.839286] audit: type=1400 audit(1463414821.673:4): apparmor="STATUS" operation="profile_load" profile="unconfined" name="/usr/lib/NetworkManager/nm-dhcp-client.action" pid=825 comm="apparmor_parser"
[ 17.839290] audit: type=1400 audit(1463414821.673:5): apparmor="STATUS" operation="profile_load" profile="unconfined" name="/usr/lib/NetworkManager/nm-dhcp-helper" pid=825 comm="apparmor_parser"
[ 17.839294] audit: type=1400 audit(1463414821.673:6): apparmor="STATUS" operation="profile_load" profile="unconfined" name="/usr/lib/connman/scripts/dhclient-script" pid=825 comm="apparmor_parser"
[ 17.841001] audit: type=1400 audit(1463414821.673:7): apparmor="STATUS" operation="profile_load" profile="unconfined" name="/usr/lib/lightdm/lightdm-guest-session" pid=824 comm="apparmor_parser"
[ 17.841005] audit: type=1400 audit(1463414821.673:8): apparmor="STATUS" operation="profile_load" profile="unconfined" name="/usr/lib/lightdm/lightdm-guest-session//chromium" pid=824 comm="apparmor_parser
但之后我无法关闭系统，因为它在启动画面上冻结。