rawhide slow like a snail because of kernel debugging?

[Michael Schwendt]

On Wed, 13 Feb 2008 16:22:08 -0800, Andrew Farris wrote:

> Michael Schwendt wrote:
> > On Wed, 13 Feb 2008 15:23:17 +0100 (CET), Adam Pribyl wrote:
> > 
> >> Got the F9 Alpha and it is, due to slowness, impossible to run it in 
> >> virtual machines where F8 is running pretty fine. I do not think this has 
> >> to do anything with kernel debug, as F8testX were also runnig pretty well. 
> >> Is there any conclusion what's wrong? This has to be pretty visible on any 
> >> hardware.
> > 
> > X. X slows down the entire show. Somewhere at the server/driver level.
> 
> You might be seeing alot of X related slowness, but its not the only thing going 
> on... I'd really like to see an argument made for why Nautilus takes a full 10s 
> to show my home directory each time (about 40 files/directories) if X is the 
> only culprit.  Its just not going to be an easy argument to make (and the cpu is 
> not under heavy load).  Why does the entire window not update until its fully 
> populated, only part of the list is going to be drawn (and X knows nothing about 
> the hidden part of that list).
> 
> There are some X slowdowns sure.  Trying to select/copy a large amount of text 
> out of the terminal is a good example of what is almost entirely X slowness; the 
> scrolling upward is fully smooth if you're not dragging a selection.

With the F9 kernel replaced with the latest F8 kernel, most visibly it
starts already at the gdm login screen. With a login window that is built
up in several slow steps. CPU spends a lot of time in sys space, and the
Xorg process' cpu usage jumps up to enormous heights often. Ordinary user
processes don't even get enough cpu power.