slub debug isn't that bad

[Bruno Wolff III]

After doing some more yum updates, I am not finding the slub debugging in 
3.8.0-0.rc4.git5.1.fc19 to be that bad. At most it is a little slower.

[Yanko Kaneti]

On Sat, 2013-01-26 at 20:49 -0600, Bruno Wolff III wrote:
> After doing some more yum updates, I am not finding the slub debugging in 
> 3.8.0-0.rc4.git5.1.fc19 to be that bad. At most it is a little slower.

Noticeably slower here.
Did a rough stopwatch benchmark of the time from pressing the enter key
on the grub menu to the time gdm-greeter shows the login screen widgets.

The difference in the timings is close to %50 
- ~20 seconda - kernel-3.8.0-0.rc4.git4.1.fc19.x86_64
- ~29 seconds - kernel-3.8.0-0.rc4.git5.1.fc19.x86_64

RS780 IGP here.

There is perceivable slugishness of the kernel spew before reaching
initramfs compared to the previous kernel
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slub debug is that bad

[Yanko Kaneti]

On Mon, 2013-01-28 at 12:51 +0200, Yanko Kaneti wrote:
> On Sat, 2013-01-26 at 20:49 -0600, Bruno Wolff III wrote:
> > After doing some more yum updates, I am not finding the slub debugging in 
> > 3.8.0-0.rc4.git5.1.fc19 to be that bad. At most it is a little slower.
>
> Noticeably slower here.
> Did a rough stopwatch benchmark of the time from pressing the enter key
> on the grub menu to the time gdm-greeter shows the login screen widgets.
>
> The difference in the timings is close to %50
> ~20 seconda - kernel-3.8.0-0.rc4.git4.1.fc19.x86_64
> ~29 seconds - kernel-3.8.0-0.rc4.git5.1.fc19.x86_64
>
> RS780 IGP here.
>
> There is perceivable slugishness of the kernel spew before reaching
> initramfs compared to the previous kernel

Continuing my unscientific grub->gdm test:
3.8.0-0.rc5.git2.1.fc19.x86_64 
  with slub_debug=-  - ~22s - and still very much usable
  without            - ~40s - graphically very slow.