ZoneMinder Forums

I have a 8 channel (with 8 bt878) card with PLX PCI6150 PCI bridge which appears to be from China.

This card worked fine in a linux server with 6 cameras connected with a board with NVIDIA chipset and AMD XP2600.

Now I'm running this card in DualCore system with P35 board and it's running inside a XEN DomU (virtual machine).

The problem is that single lines from channels are sporadic appearing in pictures of other channels. Sometimes only a half, one or two lines, sometimes a half picture.

Since the card has one bt878 for each channel and the lines are from different channels this is not an interlacing problem.

Configuration:
Xen 3.2, kernel 2.6.24-19-xen (DomU + interrupts limited to one core)
ZoneMinder v1.23.2
7 channels: PAL 720x576
1 channel: PAL 288x320
framerate: 3, alarm 5
options bttv gbuffers=32 radio=-1 tuner=4 card=77,77,77,77,77,77,77,77 autoload=0

As far as I know and tried, the valid range for gbuffers is 2-32 and everything above that defaults to something like 2 or 8.
I also tried to increase shared memory with no effects.

I'm not 100% sure, but the problem seems to load/interrupt dependent.

As far as I remember, I had similar problems (but more with hole pictures) on the other system when gbuffers was too small. But there seems to be no way to increase it.

Any ideas ?

Sound like a mis-configured card. Are you sure it is 77? Got a pic of the card?

Sorry for the delay, I had no camera.

Kodacom clone.

First, get heat sinks, or those chips will burn up.

Next, modprobe this.

options i2c_algo_bit bit_test=1
options bttv gbuffers=16 radio=-1 tuner=4 card=102,102,102,102,102,102,102,102

It will speed up booting too.

Your options do work, but not better than my old: the problem still exists.
But it really speeds up booting, thanks!

I know now I little more than before:

If I start only the DomU with ZM everything works fine, no image problems.

If I start a second DomU it still works fine, until a certain point. The problems begin, when a software using two other PCI cards (low traffic, but one is polled very often, as far as I know) and the USB controller (don't know exactly, but >10MB/s I guess). Still have to figure out which is the cause exactly, but I guess it's one of the PCI cards.

Even if it is some kind of interrupt/pci problem, I don't really understand how image data could be mixed up between different channels.
Perhaps a bug in the Xen PCI routines? But all other PCI devices seem to have no problems so far.
Some kind of buffer overflow inside the bttv driver (or ZM) due to latency problems?

Any are quiet possible.
Check your IRQ assignments:
cat /proc/interrupts

How did you configure xen DomU to use the card?
Did you exclude it in Dom0?

BTW ZoneAlarm is a firewall software, we are ZoneMinder

cat /proc/interrupts (inside DomU) I just added a PV-981 16 port PCIe card (bttv0-3), which didn't change anything. Unfortunately I did no cat /proc/interrupts before, but I guess this wouldn't have changed anything, because INT16-19 are only assignable for PCIe devices (?).
At first glance I thought perhaps two channels on the same interrupt are mixed, but they are not:
Bttv7 and btt8 are sometimes mixed e.g..
Sometimes the offset of the inserted data seems to differ so the H/V sync doesn't match. Sometimes the colors of the inserted lines are also not correct, perhaps because of an offset shift too.

cordel wrote:How did you configure xen DomU to use the card?
Did you exclude it in Dom0?

I excluded all PCI ID in Dom0 (including the corresponding bridge chip ID) and include them in the DomU (pci = ['02:00.0', ...])
Additional options:
xtra = '2 console=xvc0 noirqdebug swiotlb=force iommu=soft"
I've got a lot of other PCI hardware running inside DomUs without any problems, so I guess this is most likely not the problem.

cordel wrote:BTW ZoneAlarm is a firewall software, we are ZoneMinder

ups...how embarrassing. I edited it quickly

Changed my configuration to:
- Debian Lenny, kernel 2.6.26-2-xen-amd64
- ZM 1.23.3 (1.24.2 doesn't compile with Lenny's ffmpeg)
- dvb-multiproto v4l drivers (forgot to mention these before)
- Running everything in Dom0, after I thought DomU/shared interrupts could be the cause

-> no change, problem still exist.

Now I found these threads dealing with the same problems:
Movement artifacts
Strange Artifacting

So Xen is not the cause, I guess. Leaves only v4l or ZM....

With my current setup I do have some new problems, which doesn't exist before:

Every 52 seconds, I got timeouts for every channel on both bt878 cards (one at the time, not all together): I'm not sure whether it's linked to the image distortion problem. Since I hadn't these log messages before, I guess not.

Any ideas?

"52 seconds" problem is fixed. Not sure what is was:
I installed a debian kernel update (2.6.26-2-xen-amd64), reinstalled dvb-multiproto v4l drivers, reinstalled ffmpeg, recompiled ZM, cleared the database and the problem is gone now.

Just like to thank Lee Sharp for his help

this fixed it for me

Billy