Slow X startup and Hammering /proc/pci

[Thomas Leonard]

On Mon, 05 Jun 2006 20:36:24 +0100, Thomas Leonard wrote:

> On Mon, 05 Jun 2006 11:13:25 -0400, Phillip Ezolt wrote:
> 
>> Daniel,
>>    Can this fix be checked in?   A close to 2X speedup in the startup time
>> of the X server is mucho good.
> 
> I should point out that the 1.7s speed-up is for the startup time
> when running under strace. The speed-up when not stracing is smaller
> (but still measurable with a stop-watch, at about 0.2 s).

To be more precise, I have now tried it using:

$ time xinit -e echo hello -- ./Xorg

I ran this four times in succession for each build, ignoring the first
result in each case and recording the total time. The results are:

Stock Debian binary:

3.69
3.68
3.69

Patched with bugzilla fix:

3.59
3.60
3.59

With both the bugzilla fix and Daniel's patch:

3.48
3.48
3.51

Making the averages, rather neatly, 3.69, 3.59 and 3.49. So the saving
with both patches combined is about 5%. Sorry the savings aren't as
impressive as first thought - I guess the pci probing code was doing an
unusually high percentage of system calls, making it look worse than it
actually was.


-- 
Dr Thomas Leonard		http://rox.sourceforge.net
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