← Back to team overview

kernel-packages team mailing list archive

[Bug 1576379] Re: Macbook Air network unreliable under Xenial


** Tags added: latest-bios regression-release

You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.

  Macbook Air network unreliable under Xenial

Status in linux package in Ubuntu:

Bug description:
  This seems to be a regression from Wily.   I previously had Wily
  installed on this Macbook Air and noticed no issues with network

  Yesterday I upgraded to Xenial and networking has been unreliable ever
  since.  It seems to be OK after booting, but after a while of use
  (maybe an hour? maybe less) I start to see a lot of packets dropped
  and very high RTT per ping.

  At first I thought this may have been an issue with my ISP, as I was
  seeing THIS while pinging from my Xenial install:

   64 bytes from icmp_seq=116 ttl=40 time=28.5 ms
  64 bytes from icmp_seq=117 ttl=40 time=27.8 ms
  64 bytes from icmp_seq=122 ttl=40 time=49879 ms
  64 bytes from icmp_seq=123 ttl=40 time=49096 ms
  64 bytes from icmp_seq=124 ttl=40 time=48228 ms

  But I pinged using a network tools app on iOS connected to the same
  WiFI network (using Cable internet as the outbound connection) and
  pings were very steady in the 30ms range with no dropped packets.

  Needless to say, this makes working VERY difficult, as I am unable to
  reliably do hangouts, download files, work on GoogleDocs, or maintain
  SSH connections or VPN connections because of the unreliable network.

  So I rebooted and ran several ping tests on OSX, and the results are
  as follows:

  --- ping statistics ---
  100 packets transmitted, 100 packets received, 0.0% packet loss
  round-trip min/avg/max/stddev = 21.692/30.785/91.193/12.906 ms

  --- ping statistics ---
  100 packets transmitted, 100 packets received, 0.0% packet loss
  round-trip min/avg/max/stddev = 21.726/28.498/58.639/7.604 ms

  Then on Xenial after rebooting:
  bladernr@Rogue1:~$ uptime
   15:06:12 up 42 min,  2 users,  load average: 0.17, 0.18, 0.21

  --- ping statistics ---
  100 packets transmitted, 26 received, 74% packet loss, time 99612ms
  rtt min/avg/max/mdev = 22.456/42.526/168.247/39.368 ms

  --- ping statistics ---
  100 packets transmitted, 77 received, 23% packet loss, time 99275ms
  rtt min/avg/max/mdev = 23.043/36.687/195.534/28.956 ms

  --- ping statistics ---
  100 packets transmitted, 43 received, +6 errors, 57% packet loss, time 99525ms
  rtt min/avg/max/mdev = 23.866/339.391/4078.260/859.057 ms, pipe 5

  And this is from my phone, run around the same time the pings were run
  from Xenial showing such issues with traffic:

  Results Summary
  Average RTT	41.97 ms
  Min/Max RTT	24.05/199.18 ms
  STD Deviation	26.37 ms
  Packets (Rvcd/Sent)	104/104 (100%)

  ProblemType: Bug
  DistroRelease: Ubuntu 16.04
  Package: linux-image-4.4.0-21-generic 4.4.0-21.37
  ProcVersionSignature: Ubuntu 4.4.0-21.37-generic 4.4.6
  Uname: Linux 4.4.0-21-generic x86_64
  NonfreeKernelModules: wl
  ApportVersion: 2.20.1-0ubuntu2
  Architecture: amd64
   /dev/snd/controlC0:  bladernr   1614 F.... pulseaudio
   /dev/snd/controlC1:  bladernr   1614 F.... pulseaudio
  CurrentDesktop: Unity
  Date: Thu Apr 28 14:58:17 2016
  HibernationDevice: RESUME=UUID=1ec334c0-b29f-454a-9668-0e6f5cc2d152
  InstallationDate: Installed on 2015-10-21 (189 days ago)
  InstallationMedia: Ubuntu 15.10 "Wily Werewolf" - Release amd64 (20151020)
   Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
   Bus 001 Device 003: ID 05ac:0290 Apple, Inc. 
   Bus 001 Device 006: ID 05ac:828f Apple, Inc. 
   Bus 001 Device 002: ID 0a5c:4500 Broadcom Corp. BCM2046B1 USB 2.0 Hub (part of BCM2046 Bluetooth)
   Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
  MachineType: Apple Inc. MacBookAir6,1
  ProcFB: 0 inteldrmfb
  ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.4.0-21-generic.efi.signed root=UUID=36666d44-163a-4386-9871-83e8515efd90 ro quiet splash vt.handoff=7
   linux-restricted-modules-4.4.0-21-generic N/A
   linux-backports-modules-4.4.0-21-generic  N/A
   linux-firmware                            1.157
  SourcePackage: linux
  UpgradeStatus: No upgrade log present (probably fresh install)
  dmi.bios.date: 09/08/2015
  dmi.bios.vendor: Apple Inc.
  dmi.bios.version: MBA61.88Z.0099.B20.1509081314
  dmi.board.asset.tag: Base Board Asset Tag#
  dmi.board.name: Mac-35C1E88140C3E6CF
  dmi.board.vendor: Apple Inc.
  dmi.board.version: MacBookAir6,1
  dmi.chassis.type: 10
  dmi.chassis.vendor: Apple Inc.
  dmi.chassis.version: Mac-35C1E88140C3E6CF
  dmi.modalias: dmi:bvnAppleInc.:bvrMBA61.88Z.0099.B20.1509081314:bd09/08/2015:svnAppleInc.:pnMacBookAir6,1:pvr1.0:rvnAppleInc.:rnMac-35C1E88140C3E6CF:rvrMacBookAir6,1:cvnAppleInc.:ct10:cvrMac-35C1E88140C3E6CF:
  dmi.product.name: MacBookAir6,1
  dmi.product.version: 1.0
  dmi.sys.vendor: Apple Inc.

To manage notifications about this bug go to: