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[Doug Smythies <1254920@xxxxxxxxxxxxxxxxxx>]

I have isolated the kernel configuration differences down to:

doug@v32-serv03:~/kernel/linux-3.12.0$ diff config_def config_05
781c781
< CONFIG_X86_SYSFB=y
---
> # CONFIG_X86_SYSFB is not set
4869c4869
< CONFIG_FB_BOOT_VESA_SUPPORT=y
---
> # CONFIG_FB_BOOT_VESA_SUPPORT is not set
4900c4900
< CONFIG_FB_VESA=y
---
> # CONFIG_FB_VESA is not set

Where config_def is the default kernel configuration for the current
Trusty kernel and config_05 has 3 reversions back to the way they were
for Saucy. Each reversion by itself is not enough, they have to both (I
lump the two VESA ones into one, because one can not change one without
the other) be reverted.

Note that the console display does not work when the reversions are
done, and hasn't worked for most reversion attempts during this work. I
use ssh to access the computer.

Anticipated question: Why weren't display display issues mentioned
previously? It's kind of an important point?

Answer: Video display issues are very common on this computer when I
start messing with kernels, so I didn't think it was significant
earlier.


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

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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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