Why do I have two bluetooth services running?

起因：有时ubuntu开机后报bluetooth的错误，dmesg中也有相关的错误日志，决定肃清bluetooth，以下为转载内容，略有改动

don't know why I've got what looks like two different bluetooth managers running. From the details, it appears that bothbluemanand bluez are active.

Are both of these necessary, or can I remove one of them?

Here are the details. Running processes:

$ pgrep -fl blue
1604 /usr/sbin/bluetoothd
2052 bluetooth-applet

And the packages they apparently derive from:

cyper@cyper-pc:~$ dpkg -S bluetooth-applet
gnome-bluetooth: /etc/xdg/autostart/bluetooth-applet-unity.desktop
gnome-bluetooth: /etc/xdg/autostart/bluetooth-applet.desktop
cyper@cyper-pc:~$ dpkg -S bluetoothd
bluez: /usr/sbin/bluetoothd
bluez: /usr/share/man/man8/bluetoothd.8.gz

I believe that blueman was installed (redundantly) when I added one of the several alternate desktop managers or environments (Kubuntu, Xubuntu, Lubuntu, etc.).

More importantly, I was able to remove all of the blueman packages, and everything still functions. On the upgrade to 12.10, I didn't have any issues with it re-appearing.

在执行完评论中的命令后，一下子删除了hundreds of Mega bytes的文件，然后右上角的bluebooth图标终于不见了。

参考：
http://askubuntu.com/questions/171977/why-do-i-have-two-bluetooth-services-running
http://askubuntu.com/questions/305856/how-to-remove-bluetooth-manager-in-xubuntu