Re: [libdc1394-devel] Heavy packet dropping on an 8 processor rig

[David P. <da...@pr...>]

Damien Douxchamps wrote:
> Hi all,
> 
> I experience very strong packet dropping on an 8 proc machine (dual
> quad-core Xeon). I have limited the machine to 1GB of RAM (it has 4) and
> to a single CPU but the problem remains. I'm using a one IIDC cameras on
> a single interface card (unibrain 1394b card in a PCI64 slot).
> 

If I were you I'd see if I could find a PCI-E firewire interface card to 
eliminate at least some of the mobo chipset, although these things are 
increasingly integrated these days.

As David Moore suggested, getting a raw bus capture would be ideal, I've 
only ever done this with specialised hardware that can capture at full 
firewire speeds in real time at work, but it cant be that hard to use a 
slave PC to do the same thing, although you may not see physical signal 
level errors if they are occurring. Good luck!

David Prime



> The problem appears as jumping images (if the packet size is not a
> multiple of the line size) or images with missing lines (if packet size
> == line size). Several packets are missed every frame, and sometimes
> this causes the actual framerate to drop below 3 while it should be 30.
> That's quite a lot of dropped packets... OTOH at low bytes-per-packet
> there is no packet dropping at all.
> 
> The packet dropping is roughly proportional to the bandwidth usage. If a
> second camera is used, a higher bytes-per-packet on one camera will
> affect the packet dropping on the second camera too, so I don't think
> that the packet dropping is related to cables or cameras (confirmed by
> changing cables, etc...) Changing the interface card to a more classic
> 1394a 32bit PCI card does not change anything. Using two cards with one
> camera on each card has no effect either. IMHO this indicates a problem
> downstream from the 1394 card, iow the mobo chipset or its drivers (the
> chipset is a rather new 5000V from Intel). Before sending this bug
> report to 'lower levels' I'd like to know if anyone has experienced that
> before.
> 
> I'm using libdc1394 (latest SVN) on a 2.6.20 kernel (2.6.17 has the same
> problem). The distro is a fresh install of xubuntu, but the same problem
> occurs on an older ubuntu. There is no error/warning reported in the
> logs. The computer has no significant load (video capture itself is
> negligible). Details about the platform follow below.
> 
> Any help would be greatly appreciated...
> 
> Damien
> 
> 
> 
> $ uname -a 
> Linux chunky 2.6.20-15-generic #2 SMP Sun Apr 15 07:36:31 UTC 2007 i686 GNU/Linux
> 
> $ lspci 
> 00:00.0 Host bridge: Intel Corporation 5000V Chipset Memory Controller Hub (rev 92)
> 00:02.0 PCI bridge: Intel Corporation 5000 Series Chipset PCI Express x8 Port 2-3 (rev 92)
> 00:03.0 PCI bridge: Intel Corporation 5000 Series Chipset PCI Express x4 Port 3 (rev 92)
> 00:08.0 System peripheral: Intel Corporation 5000 Series Chipset DMA Engine (rev 92)
> 00:10.0 Host bridge: Intel Corporation 5000 Series Chipset Error Reporting Registers (rev 92)
> 00:10.1 Host bridge: Intel Corporation 5000 Series Chipset Error Reporting Registers (rev 92)
> 00:10.2 Host bridge: Intel Corporation 5000 Series Chipset Error Reporting Registers (rev 92)
> 00:11.0 Host bridge: Intel Corporation 5000 Series Chipset Reserved Registers (rev 92)
> 00:13.0 Host bridge: Intel Corporation 5000 Series Chipset Reserved Registers (rev 92)
> 00:15.0 Host bridge: Intel Corporation 5000 Series Chipset FBD Registers (rev 92)
> 00:16.0 Host bridge: Intel Corporation 5000 Series Chipset FBD Registers (rev 92)
> 00:1c.0 PCI bridge: Intel Corporation 631xESB/632xESB/3100 Chipset PCI Express Root Port 1 (rev 09)
> 00:1d.0 USB Controller: Intel Corporation 631xESB/632xESB/3100 Chipset UHCI USB Controller #1 (rev 09)
> 00:1d.1 USB Controller: Intel Corporation 631xESB/632xESB/3100 Chipset UHCI USB Controller #2 (rev 09)
> 00:1d.2 USB Controller: Intel Corporation 631xESB/632xESB/3100 Chipset UHCI USB Controller #3 (rev 09)
> 00:1d.3 USB Controller: Intel Corporation 631xESB/632xESB/3100 Chipset UHCI USB Controller #4 (rev 09)
> 00:1d.7 USB Controller: Intel Corporation 631xESB/632xESB/3100 Chipset EHCI USB2 Controller (rev 09)
> 00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev d9)
> 00:1f.0 ISA bridge: Intel Corporation 631xESB/632xESB/3100 Chipset LPC Interface Controller (rev 09)
> 00:1f.1 IDE interface: Intel Corporation 631xESB/632xESB IDE Controller (rev 09)
> 00:1f.2 IDE interface: Intel Corporation 631xESB/632xESB/3100 Chipset SATA Storage Controller IDE (rev 09)
> 00:1f.3 SMBus: Intel Corporation 631xESB/632xESB/3100 Chipset SMBus Controller (rev 09)
> 01:00.0 PCI bridge: Intel Corporation 6311ESB/6321ESB PCI Express Upstream Port (rev 01)
> 01:00.3 PCI bridge: Intel Corporation 6311ESB/6321ESB PCI Express to PCI-X Bridge (rev 01)
> 02:00.0 PCI bridge: Intel Corporation 6311ESB/6321ESB PCI Express Downstream Port E1 (rev 01)
> 02:01.0 PCI bridge: Intel Corporation 6311ESB/6321ESB PCI Express Downstream Port E2 (rev 01)
> 02:02.0 PCI bridge: Intel Corporation 6311ESB/6321ESB PCI Express Downstream Port E3 (rev 01)
> 04:00.0 VGA compatible controller: nVidia Corporation NV43 [GeForce 6600] (rev a2)
> 05:00.0 Ethernet controller: Intel Corporation 80003ES2LAN Gigabit Ethernet Controller (Copper) (rev 01)
> 05:00.1 Ethernet controller: Intel Corporation 80003ES2LAN Gigabit Ethernet Controller (Copper) (rev 01)
> 06:02.0 FireWire (IEEE 1394): Texas Instruments TSB82AA2 IEEE-1394b Link Layer Controller (rev 01)
> 09:0d.0 Multimedia audio controller: Creative Labs SB Live! EMU10k1 (rev 07)
> 09:0d.1 Input device controller: Creative Labs SB Live! Game Port (rev 07)
> 
> $ lsmod
> Module                  Size  Used by 
> nls_iso8859_1           5120  1 
> nls_cp437               6784  1 
> vfat                   14208  1 
> fat                    53916  1 vfat
> usb_storage            72256  1 
> libusual               17936  1 usb_storage
> raw1394                30328  0 
> video1394              19672  0 
> ohci1394               36528  1 video1394
> ppdev                  10116  0 
> acpi_cpufreq           10056  7 
> cpufreq_conservative     8200  0 
> cpufreq_ondemand        9228  1 
> cpufreq_powersave       2688  0 
> cpufreq_stats           7360  0 
> freq_table              5792  3 acpi_cpufreq,cpufreq_ondemand,cpufreq_stats
> cpufreq_userspace       5408  0 
> sony_acpi               6284  0 
> tc1100_wmi              8068  0 
> dev_acpi               12292  0 
> pcc_acpi               13184  0 
> video                  16388  0 
> container               5248  0 
> battery                10756  0 
> dock                   10268  0 
> asus_acpi              17308  0 
> button                  8720  0 
> ac                      6020  0 
> backlight               7040  1 asus_acpi
> sbs                    15652  0 
> i2c_ec                  5888  1 sbs
> reiserfs              247680  1 
> ipv6                  268704  24 
> sbp2                   23812  0 
> parport_pc             36388  0 
> lp                     12452  0 
> parport                36936  3 ppdev,parport_pc,lp
> fuse                   46612  0 
> snd_emu10k1_synth       8192  0 
> snd_emux_synth         35456  1 snd_emu10k1_synth
> snd_seq_virmidi         7936  1 snd_emux_synth
> snd_seq_midi_emul       7680  1 snd_emux_synth
> snd_emu10k1           121248  3 snd_emu10k1_synth
> snd_ac97_codec         98336  1 snd_emu10k1
> ac97_bus                3200  1 snd_ac97_codec
> snd_pcm_oss            44544  0 
> snd_mixer_oss          17408  1 snd_pcm_oss
> af_packet              23816  6 
> snd_pcm                79876  3 snd_emu10k1,snd_ac97_codec,snd_pcm_oss
> snd_page_alloc         10888  2 snd_emu10k1,snd_pcm
> snd_util_mem            5760  2 snd_emux_synth,snd_emu10k1
> snd_hwdep               9988  2 snd_emux_synth,snd_emu10k1
> nvidia               6837108  22 
> snd_seq_dummy           4740  0 
> snd_seq_oss            32896  0 
> agpgart                35400  1 nvidia
> i2c_core               22784  2 i2c_ec,nvidia
> snd_seq_midi            9600  0 
> snd_rawmidi            25472  3 snd_seq_virmidi,snd_emu10k1,snd_seq_midi
> snd_seq_midi_event      8448  3 snd_seq_virmidi,snd_seq_oss,snd_seq_midi
> snd_seq                52592  9 snd_emux_synth,snd_seq_virmidi,snd_seq_midi_emul,snd_seq_dummy,snd_seq_oss,snd_seq_midi,snd_seq_midi_event
> snd_timer              23684  3 snd_emu10k1,snd_pcm,snd_seq
> snd_seq_device          9100  8 snd_emu10k1_synth,snd_emux_synth,snd_emu10k1,snd_seq_dummy,snd_seq_oss,snd_seq_midi,snd_rawmidi,snd_seq
> serio_raw               7940  0 
> snd                    54020  17 snd_emux_synth,snd_seq_virmidi,snd_emu10k1,snd_ac97_codec,snd_pcm_oss,snd_mixer_oss,snd_pcm,snd_hwdep,snd_seq_oss,snd_rawmidi,snd_seq,snd_timer,snd_seq_device
> shpchp                 34324  0 
> emu10k1_gp              4736  0 
> gameport               16520  2 emu10k1_gp
> psmouse                38920  0 
> pci_hotplug            32576  1 shpchp
> soundcore               8672  1 snd
> pcspkr                  4224  0 
> tsdev                   8768  0 
> evdev                  11008  3 
> ext3                  133128  4 
> jbd                    59816  1 ext3
> mbcache                 9604  1 ext3
> sg                     36252  0 
> sr_mod                 17060  0 
> sd_mod                 23428  12 
> cdrom                  37664  1 sr_mod
> generic                 5124  0 [permanent]
> ata_generic             9092  0 
> usbhid                 26592  0 
> hid                    27392  1 usbhid
> e1000                 126016  0 
> ehci_hcd               34188  0 
> ata_piix               15492  6 
> libata                125720  2 ata_generic,ata_piix
> scsi_mod              142348  6 usb_storage,sbp2,sg,sr_mod,sd_mod,libata
> ieee1394              299448  4 raw1394,video1394,ohci1394,sbp2
> uhci_hcd               25360  0 
> usbcore               134280  6 usb_storage,libusual,usbhid,ehci_hcd,uhci_hcd
> thermal                14856  0 
> processor              31048  2 acpi_cpufreq,thermal
> fan                     5636  0 
> fbcon                  42656  0 
> tileblit                3584  1 fbcon
> font                    9216  1 fbcon
> bitblit                 6912  1 fbcon
> softcursor              3200  1 bitblit
> vesafb                  9220  0 
> capability              5896  0 
> commoncap               8192  1 capability
> 
>