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[Doug Smythies <1254920@xxxxxxxxxxxxxxxxxx>]

The issue is that all of those kernels work, the issue does not appear
until the kernel configuration changes between saucy and trusty, as
mentioned in my original posting.

Without even knowing a good starting point, I tried a kernel bi-section,
but with the "new configuration" and went back as far as I could. I.E. I
was starting to get more and more kernels that wouldn't work at all, or
even boot. I got back as far as what the bi-section stuff called "linux-
image-3.8.0-c05" and the problem persisted.

So, I'm suggesting that the CPU utilization accounting issue has been
there for quite some time, but perhaps has been masked by Ubuntu's
kernel configuration (or I failed to notice it when the computer was
running 13.10 and the display was also working).

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https://bugs.launchpad.net/bugs/1254920

Title:
  CPU utilization / accounting issues

Status in “linux” package in Ubuntu:
  Confirmed

Bug description:
  The issue is on a Trusty 32 bit server edition. It is the very very
  old computer that I use for minimum requirements testing.

  The issue is CPU user, sys, idle, and wait information makes absolutely no sense at all.
  For example with the commands "top" or "vmstat"
  I believe I have isolated the issue down to kernel configuration differences between Saucy and Trusty. I used the two otherwise same kernels from the ppa to come to this conclusion (after many many other kernels and such were tried). References:

  http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.12-saucy/
  http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.12-trusty/

  While there are a lot of configuration differences that are obviously
  not the issue (or so I think), there are many that I don't know if
  they could be or not. The computer I am using is too pathetic to
  compile the kernel (it takes 34 hours, and then it gives up before
  finishing anyhow).

  I will attach the config difference file in a moment.

  Automatic bug stuff has never worked for me on any of my computers,
  but I'll attach the other stuff asked for shortly.

  Example of expected vmstat output (server relatively idle):

  doug@test-smy:~/configs$ vmstat 20
  procs -----------memory---------- ---swap-- -----io---- -system-- ----cpu----
   r  b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id wa
   0  0    292   3952   4936  48668    0    0   247     5  265  151 14  7 77  2
   1  0    292   3912   4944  48708    0    0     2     2  252   50  0  0 100  0
   1  0    292   3912   4944  48708    0    0     0     0  252   47  0  0 100  0
   0  0    292   3900   4952  48708    0    0     0     2  252   49  0  0 99  1
   0  0    292   3900   4952  48708    0    0     0     1  252   51  0  0 100  0
   0  0    292   2636   4960  49928    0    0    61     1  253   56  0  0 99  1

  Example of vmstat output now (server idle):

  doug@test-smy:~$ vmstat 20
  procs -----------memory---------- ---swap-- -----io---- -system-- ----cpu----
   r  b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id wa
   0  0   5312   5544   3408  47900    8   22  1412    78 24253 4209 44 30  9 17
   0  0   5312   5528   3416  47916    0    0     0     1  252   41  0  0 40 60
   0  0   5312   5528   3416  47916    0    0     0     0  251   40  0 25  0 75
   0  0   5312   5528   3416  47916    0    0     0     0  252   39 17  0 50 33
   0  0   5312   5528   3416  47916    0    0     0     0  252   39  0  0 40 60
   0  0   5312   5516   3424  47916    0    0     0     1  252   41  0 25  0 75
   0  0   5312   5516   3424  47916    0    0     0     0  252   40  0 17 33 50

  doug@test-smy:~$ lsb_release -a
  No LSB modules are available.
  Distributor ID: Ubuntu
  Description:    Ubuntu Trusty Tahr (development branch)
  Release:        14.04
  Codename:       trusty
  doug@test-smy:~$ uname -a
  Linux test-smy 3.12.0-4-generic #10-Ubuntu SMP Thu Nov 21 22:11:22 UTC 2013 i686 i686 i686 GNU/Linux

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