kernel-packages team mailing list archive

[Timothy Pearson <kb9vqf@xxxxxxxxxxxxxxxxxxxx>]

** Bug watch added: Debian Bug tracker #817063
   http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=817063

** Also affects: linux via
   http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=817063
   Importance: Unknown
       Status: Unknown

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https://bugs.launchpad.net/bugs/1536837

Title:
  Severe performance regression in Infiniband or IPoIB

Status in Linux:
  Unknown
Status in linux package in Ubuntu:
  Triaged

Bug description:
  When upgrading to the latest 4.4 test kernel from mainline
  development, all IPoIB links showed a severe performance regression as
  compared with kernel 4.2.  The bandwidth of each link dropped from
  around 3Gbps to around 3Mbps (3 orders of magnitude worse!); reverting
  to the 4.2 kernel immediately fixed this problem.

  The 4.3 kernel from Debian does not appear to suffer from this
  regression.  The regression shows up on both IB ports of the Mellanox
  MT25208 controller.  Other hardware has not been tested.

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