This bug is missing log files that will aid in diagnosing the problem.
>From a terminal window please run:

apport-collect 1606147

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable
to run this command, please add a comment stating that fact and change
the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the
Ubuntu Kernel Team.

** Changed in: linux (Ubuntu)
       Status: New => Incomplete

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https://bugs.launchpad.net/bugs/1606147

Title:
  [APL][SAUCE] System works slowly due to a monitor bug

Status in linux package in Ubuntu:
  Incomplete

Bug description:
  [Impact]

  We've found a bug on some Apollo Lake system makes it runs very slow.
  From upstream it is caused by following reason:

  "Monitored cached line may not wake up from mwait on certain Goldmont
  based CPUs. This patch will avoid calling
  current_set_polling_and_test() and thereby not set the TIF_ flag. The
  result is that we'll always send IPIs for wakeups."

  [Fix]

  Upstream already provided a workaround[1] to fix this problem. This
  patches haven't been merged in latest(v4.7) release but already in
  linux-next.

  To fix this issue in Xenial it also needs another commit introduces
  macros use in the workaround:

  commit 970442c599b22ccd644ebfe94d1d303bf6f87c05
  Author: Dave Hansen <d...@sr71.net>
  Date:   Thu Jun 2 17:19:27 2016 -0700

      x86/cpu/intel: Introduce macros for Intel family numbers

  This workaround checks CPU families and certain features, so no
  further regressions is expected

  [1]: https://lkml.org/lkml/2016/7/6/469

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