rawhide slow like a snail because of kernel debugging?

[Christopher Brown]

On 10/02/2008, Michael Schwendt <mschwendt.tmp0701.nospam at arcor.de> wrote:
> It has begun some weeks ago in rawhide and is the same in F9 Alpha,
> which I installed from jigdo CD images.
>
> The entire system is slow whatever it does. Loadavg jumps up
> quickly. When running a simple yum update, loadavg goes above 6. User
> processes don't seem to get as much cpu power as would be possible.
> Windows take seconds to open. The GNOME Desktop is not as responsive
> as in F8 either. Opening dialogs, clicking buttons, there seems to be
> a penalty on everything. It's unbearable. Testing rawhide or F9 is no
> fun at all. Why is this? I remember that during Fedora Core test
> releases various kernel debugging features are enabled. Is this the
> reason also this time? Has it become much more cpu power hungry than
> e.g. with FC7 and older?

>From the wiki:

In Rawhide/devel kernels (and in -debug flavors of released kernels),
Fedora uses the SLUB allocator with full slab debugging enabled by
default. The debugging might cause problems in some rare cases: memory
allocations can fail, causing the system to panic. Slab debugging can
be disabled with the option slub_debug=-  (a single minus sign.) Note,
that this option will hide an actual bug that really should be
reported and fixed rather than worked around.

Cheers
-- 
Christopher Brown

http://www.chruz.com