[LAU] 3.10-rt kernels unusable

[Ralf Mardorf]

Hi Fernando, Victor and Raffaele,

On Wed, 2013-08-28 at 08:12 +0200, Raffaele Morelli wrote:
> Did you enable dynticks? 32 or 64? 
> I've been experiencing many freezes with 3.10.x

The kernel build for Arch was build using it's default AUR config, the
kernel build for Ubuntu Quantal is build using a different config, but
not regarding to dynticks, NO_HZ is enabled. It's on 64 bit
architecture.

[rocketmouse at archlinux ~]$ grep _HZ /mnt/q/boot/config-3.10.9-rt5
CONFIG_NO_HZ_COMMON=y
# CONFIG_HZ_PERIODIC is not set
CONFIG_NO_HZ_IDLE=y
# CONFIG_NO_HZ_FULL is not set
CONFIG_NO_HZ=y
# CONFIG_HZ_100 is not set
# CONFIG_HZ_250 is not set
# CONFIG_HZ_300 is not set
CONFIG_HZ_1000=y
CONFIG_HZ=1000
[rocketmouse at archlinux ~]$ grep _HZ linux-rt/config.x86_64
CONFIG_NO_HZ_COMMON=y
# CONFIG_HZ_PERIODIC is not set
CONFIG_NO_HZ_IDLE=y
# CONFIG_NO_HZ_FULL is not set
CONFIG_NO_HZ=y
# CONFIG_HZ_100 is not set
# CONFIG_HZ_250 is not set
# CONFIG_HZ_300 is not set
CONFIG_HZ_1000=y
CONFIG_HZ=1000
[rocketmouse at archlinux ~]$ diff /mnt/q/boot/config-3.10.9-rt5 linux-rt/config.x86_64 | grep CONFIG_MK8
< CONFIG_MK8=y
> # CONFIG_MK8 is not set

I subscribed to linux-rt-users at vger.kernel.org on Monday, but I've got
no time to check log files etc., perhaps next month.

FWIW for the non-rt-kernel NO_HZ is enabled too.

[rocketmouse at archlinux ~]$ uname -rm
3.10.9-1-ARCH x86_64
[rocketmouse at archlinux ~]$ zgrep _HZ /proc/config.gz
CONFIG_NO_HZ_COMMON=y
# CONFIG_HZ_PERIODIC is not set
CONFIG_NO_HZ_IDLE=y
# CONFIG_NO_HZ_FULL is not set
CONFIG_NO_HZ=y
CONFIG_RCU_FAST_NO_HZ=y
# CONFIG_HZ_100 is not set
# CONFIG_HZ_250 is not set
CONFIG_HZ_300=y
# CONFIG_HZ_1000 is not set
CONFIG_HZ=300

Regards,
Ralf