[mythtv-users] spontaneous reboots after upgrade & move to Ubuntu - IVTV/pre-emptive kernel locks?
peterw at tux.org
Sat Sep 8 00:01:34 UTC 2007
A couple weeks ago I upgraded my 0.19 system (based on Fedora Core 4
i386 & Jarod's guide) to 0.20.x on Ubuntu 7.04 amd64, in preparation for
The system has been spontaneously rebooting ever since -- uptime between
7 minutes and 9 hours. Before this change, it was rock solid. Sometimes
the HD3000/DVB tuner would fail (and record 0 bytes), but the hardware &
OS were very stable. It /seems/ less stable when recording SD shows via
IVTV and my PVR 500, but it /has/ successfully recorded some two hour
movies, so it's not failing predictably.
I've tried to test a number of components and came across the
MythTV/IVTV wiki entry warning "Do /not/ attempt to enable pre-emptive
kernel locks in your kernel configuration--the ivtv modules do not get
along with them and will cause /spontaneous reboots/." Is this possibly
what I'm seeing? How can I tell: first, if my amd64 kernel supports
pre-emptive kernel locks, and, second, if that's enabled? And can I
disable them through /proc or a boot option?
What has changed:
I replaced two older ATA drives (replaced Seagate 200G and 250G with a
matched pair of Seagate 500G), added a 1GB memory module (now has 2 GB
RAM), and installed an additional 120mm case fan to help cool the drives
& system. Instead of Fedora Code 4 i386 on /dev/hda I now have Ubuntu
7.04 amd64 running on md raid (raid1 for /boot and /) -- which also
means many upgraded software packages, including IVTV and NVidia
drivers. I've replaced the 18 month old Antec TruePower II 550w power
supply with a new Sea Sonic 550w supply.
The RAM checked out fine with an ~18 hour memtest86+ run. No errors have
been reported on the drives by partitioning tools, SMART tools, etc.
I've tried removing the new RAM, moving the RAM around and disconnecting
the new case fan. I have disconnected a seldom-used SCSI tape drive and
physically removed its host adapter. I switched SATA power cables for
the SATA drives that I am still using. I have run StressCPU from UBCD
for over three hours without trouble. I have not tried disconnecting
either of the new 500G hard drives. The system temperature looks OK.
There's no lm_sensors support, but when rebooting after normal use, the
system temp is usually around 40 C and the CPU temp around 45 C. As
stated above, I have replaced the power supply. I have run a 'cp' for a
4 GB file in a while  loop to test the disk/md/lvm.
Considering the previous stability, the new power supply, the success
with memtest86+, and the results of my hardware tests, it seems very
plausible that I'm having software trouble.
Athlon64 with 2 ATA and 2 SATA hard drives, using LVM atop "md" RAID1
arrays for the MythTV recordings (MySQL data is on the simple raid1 md
array for /). PS is a 550w Sea Sonic S12, which gets AC through an APC
UPS. Video is an Nvidia 6200 LE (AGP), feeding the TV via DVI, using the
Nvidia binary driver (rev 9631, I believe -- the version suggested by
Ubuntu's proprietary driver manager app, using NvAGP "2" for better
picture quality). Three PCI cards: a pcHDTV HD3000 tuner used for ATSC,
a Hauppauge PVR-500 used for SD/cable, and an old Ensoniq 1371 sound
card. One DVD-RW on the second IDE channel, and, yes, a floppy drive.
I'm running the Ubuntu kernel "2.6.20-16-generic #2 SMP Thu Jun 7
19:00:28 UTC 2007 x86_64 GNU/Linux" and Ubuntu's IVTV 0.10.1. The config
for that kernel (in /boot) has the following "preempt" kernel settings:
# CONFIG_PREEMPT_NONE is not set
# CONFIG_PREEMPT is not set
Also, sometimes Ubuntu fails to boot, dropping me to a busybox prompt
(looks like this problem, but the piix initramfs approach has not
sufficed for me:
I haven't tried the quiet/splash/irqpoll boot settings yet). With the
UPS, I'm not too worried about this; I only mention it in case someone
thinks it relevant to the spontaneous reboots.
Any help appreciated!
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the mythtv-users