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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
Schedules Direct.<br>
<br>
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. <br>
<br>
I've tried to test a number of components and came across
the MythTV/IVTV wiki entry warning "Do <i>not</i> attempt to enable
pre-emptive kernel locks in your kernel
configuration--the ivtv modules do not get along with them and will
cause <i>spontaneous reboots</i>." 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?<br>
<br>
What has changed: <br>
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.<br>
<br>
Troubleshooting:<br>
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.<br>
<br>
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.<br>
<br>
System details:<br>
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:<br>
<br>
# CONFIG_PREEMPT_NONE is not set<br>
CONFIG_PREEMPT_VOLUNTARY=y<br>
# CONFIG_PREEMPT is not set<br>
CONFIG_PREEMPT_BKL=y<br>
<br>
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:
<a class="moz-txt-link-freetext" href="https://bugs.launchpad.net/ubuntu/+source/linux-source-2.6.20/+bug/106864">https://bugs.launchpad.net/ubuntu/+source/linux-source-2.6.20/+bug/106864</a>;
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.<br>
<br>
Any help appreciated!<br>
<br>
-Peter<br>
<br>
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