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  • processes, interrupts, and cpus

    From fxkl47BF@protonmail.com@21:1/5 to All on Tue Aug 20 20:10:01 2024
    i have a video capture card with 4 separate chips
    when i start up i get bttv0 - bttv3
    i'm getting a lot of errors in syslog on bttv2 and bttv3
    like
    bttv: 2: timeout: drop=3888442 irq=27910652/28054718, risc=338f048c, bits: HSYNC
    bttv: 3: timeout: drop=3940265 irq=27929862/27929862, risc=33adc01c, bits: HSYNC

    could it be related to interrupts and cpus
    cat /proc/interrupts
    CPU0 CPU1 CPU2 CPU3
    16: 0 26950435 0 0 IO-APIC 16-fasteoi bttv1
    17: 0 0 28079982 0 IO-APIC 17-fasteoi bttv2
    18: 0 0 27950635 0 IO-APIC 18-fasteoi i801_smbus, bttv3
    19: 66003 0 0 0 IO-APIC 19-fasteoi bttv0

    i notice bttv2 and bttv3 are on the same cpu
    and bttv3 is sharing an interrupt
    is this related to my timeout errors
    if so is it correctable

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Dan Ritter@21:1/5 to fxkl47BF@protonmail.com on Wed Aug 21 00:30:01 2024
    fxkl47BF@protonmail.com wrote:
    i have a video capture card with 4 separate chips
    when i start up i get bttv0 - bttv3
    i'm getting a lot of errors in syslog on bttv2 and bttv3
    like
    bttv: 2: timeout: drop=3888442 irq=27910652/28054718, risc=338f048c, bits: HSYNC
    bttv: 3: timeout: drop=3940265 irq=27929862/27929862, risc=33adc01c, bits: HSYNC

    could it be related to interrupts and cpus
    cat /proc/interrupts
    CPU0 CPU1 CPU2 CPU3
    16: 0 26950435 0 0 IO-APIC 16-fasteoi bttv1
    17: 0 0 28079982 0 IO-APIC 17-fasteoi bttv2
    18: 0 0 27950635 0 IO-APIC 18-fasteoi i801_smbus, bttv3
    19: 66003 0 0 0 IO-APIC 19-fasteoi bttv0

    i notice bttv2 and bttv3 are on the same cpu
    and bttv3 is sharing an interrupt
    is this related to my timeout errors
    if so is it correctable

    Depending on the hardware -- I don't remember the ins and outs
    of most video capture cards these days -- you should be able to
    set the interrupt per card either in hardware or at kernel
    module load time.

    This could certainly be an issue, especially on a relatively
    low-powered machine; if you don't have the irqbalance daemon
    installed, you might try that first.

    -dsr-

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From fxkl47BF@protonmail.com@21:1/5 to Dan Ritter on Wed Aug 21 01:40:01 2024
    On Tue, 20 Aug 2024, Dan Ritter wrote:

    fxkl47BF@protonmail.com wrote:
    i have a video capture card with 4 separate chips
    when i start up i get bttv0 - bttv3
    i'm getting a lot of errors in syslog on bttv2 and bttv3
    like
    bttv: 2: timeout: drop=3888442 irq=27910652/28054718, risc=338f048c, bits: HSYNC
    bttv: 3: timeout: drop=3940265 irq=27929862/27929862, risc=33adc01c, bits: HSYNC

    could it be related to interrupts and cpus
    cat /proc/interrupts
    CPU0 CPU1 CPU2 CPU3
    16: 0 26950435 0 0 IO-APIC 16-fasteoi bttv1
    17: 0 0 28079982 0 IO-APIC 17-fasteoi bttv2
    18: 0 0 27950635 0 IO-APIC 18-fasteoi i801_smbus, bttv3
    19: 66003 0 0 0 IO-APIC 19-fasteoi bttv0

    i notice bttv2 and bttv3 are on the same cpu
    and bttv3 is sharing an interrupt
    is this related to my timeout errors
    if so is it correctable

    Depending on the hardware -- I don't remember the ins and outs
    of most video capture cards these days -- you should be able to
    set the interrupt per card either in hardware or at kernel
    module load time.

    This could certainly be an issue, especially on a relatively
    low-powered machine; if you don't have the irqbalance daemon
    installed, you might try that first.

    -dsr-


    i installed irqbalance and it dramatically reduced the errors
    from 2-3 a minute to 1 every 3-4 minutes

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Dan Ritter@21:1/5 to fxkl47BF@protonmail.com on Wed Aug 21 02:00:01 2024
    fxkl47BF@protonmail.com wrote:
    On Tue, 20 Aug 2024, Dan Ritter wrote:

    fxkl47BF@protonmail.com wrote:
    i have a video capture card with 4 separate chips
    when i start up i get bttv0 - bttv3
    i'm getting a lot of errors in syslog on bttv2 and bttv3
    like
    bttv: 2: timeout: drop=3888442 irq=27910652/28054718, risc=338f048c, bits: HSYNC
    bttv: 3: timeout: drop=3940265 irq=27929862/27929862, risc=33adc01c, bits: HSYNC

    could it be related to interrupts and cpus
    cat /proc/interrupts
    CPU0 CPU1 CPU2 CPU3
    16: 0 26950435 0 0 IO-APIC 16-fasteoi bttv1
    17: 0 0 28079982 0 IO-APIC 17-fasteoi bttv2
    18: 0 0 27950635 0 IO-APIC 18-fasteoi i801_smbus, bttv3
    19: 66003 0 0 0 IO-APIC 19-fasteoi bttv0

    i notice bttv2 and bttv3 are on the same cpu
    and bttv3 is sharing an interrupt
    is this related to my timeout errors
    if so is it correctable

    Depending on the hardware -- I don't remember the ins and outs
    of most video capture cards these days -- you should be able to
    set the interrupt per card either in hardware or at kernel
    module load time.

    This could certainly be an issue, especially on a relatively
    low-powered machine; if you don't have the irqbalance daemon
    installed, you might try that first.

    -dsr-


    i installed irqbalance and it dramatically reduced the errors
    from 2-3 a minute to 1 every 3-4 minutes

    OK, now you know it's an IRQ sharing problem. Look up docs for
    your card and driver module and see if you can push them to
    non-competing IRQs.

    If they are PCI rather than PCIe cards, you may need to
    physically switch slots, or there may be a BIOS change
    available.

    -dsr-

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)