Bluetooth – Is Bluetooth Slowing Down Ubuntu 16.04 Startup?


I've recently upgraded from Xubuntu 14.04 to Xubuntu 16.04 on Lenovo T450s. The upgrade was uneventful and the system's been running very well, so kudos to the dev team behind it.

However the startup and shutdown times have been extended by about 40-50 seconds. Blame is not showing the culprit:

$ sudo systemd-analyze blame

  6.961s NetworkManager-wait-online.service
  1.920s docker.service
   767ms dev-sda1.device
   324ms gpu-manager.service

However, dmesg appears to point at the bluetooth subsystem:

[3.807429] iwlwifi 0000:03:00.0 wlan1: renamed from wlan0
[6.037784] psmouse serio2: trackpoint: IBM TrackPoint
[6.235993] input: TPPS/2 IBM TrackPoint as 
[92.865487] Bluetooth: BNEP (Ethernet Emulation) ver 1.3
[92.865491] Bluetooth: BNEP filters: protocol multicast
[92.865496] Bluetooth: BNEP socket layer initialized

Has anyone else experience this? Any suggestions how to fix the problem?

(I already checked other suggestions like swap partition having a different UUID in fstab vs blkid)

Best Answer

The problem is not necessarily related to the Bluetooth. Something slow is happening during those two dmesg rows.

I had the same problem after a fresh install to a new SSD drive. It turned out that during the install process Ubuntu found the older HDD's swap partition and registered that in /etc/fstab. After I have removed the older HDD the swap partition was naturally not available and Ubuntu was waiting there for more than a minute without any dmesg row to appear. When I deleted the HDD's swap partition from /etc/fstab the boot became less than 10 seconds.

You may have the same cause or some hardware- but non necessarily Bluetooth-related problem.

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