Bug#472180: Bug #472180: Xprt hogging CPU

[Drew Parsons <dparsons@debian.org>]

Here is the top of a gprof analysis.

I'm wondering if the Xkb references indicate that it is the problem.  I
can hypothesise that some changes in the general Xserver code touched
upon Xkb, expecting the DDX to initialise it appropriately.  Since
Xprint does not use Xkb, it doesn't handle it in any explicit way.
Could Xkb be spinning, waiting for the Xprint DDX to tell it to go away
and stop being annoying?  This Xkb hypothesis is corroborated by
https://bugs.freedesktop.org/show_bug.cgi?id=13063


Function/Method                 Count Total (s)    % Self (s) Total
ms/call Self ms/call
Dispatch                            1   0.150 68.200  0.030
150.000       30.000
WaitForSomething             1444561    0.060 27.300  0.060
0.000        0.000
__i686.get_pc_thunk.bx              0   0.060 27.300  0.060
0.000        0.000
FlushIfCriticalOutputPending 1444561    0.060 27.300  0.060
0.000        0.000
XkbRF_LoadRules                     1   0.010 4.500   0.000
10.000        0.000
XkbInitKeyboardDeviceStruct         1   0.010 4.500   0.000
10.000        0.000
XkbDDXNamesFromRules                1   0.010 4.500   0.000
10.000        0.000
GetInputLine                     833    0.010 4.500   0.010
0.010        0.010
CoreKeyboardProc                    3   0.010 4.500   0.000
3.330        0.000
InitAndStartDevices                 1   0.010 2.300   0.000
5.000        0.000
EnableDevice                        4   0.000 1.500   0.000
0.830        0.000
CloseDownDevices                    1   0.000 1.500   0.000
3.330        0.000
CloseDevice                         4   0.000 1.500   0.000
0.830        0.000
ActivateDevice                      4   0.000 1.500   0.000
0.830        0.000
InitCoreDevices                     1   0.000 0.800   0.000
1.670        0.000