[asterisk-users] [hylafax-users] asterisk, iaxmodem, hylafax quality problem

[Thomas Kenyon]

Lee Howard wrote:
> Artifex Maximus wrote:
> 
>> zttest is often on 99.975586% with final result:
>> --- Results after 67 passes ---
>> Best: 99.987793 -- Worst: 99.951172 -- Average: 99.973764
> 
> 
> This is unacceptable for faxing, and it is evidence of the underlying
> problem also causing your faxes to come through with poor quality.
> 
Sadly both my production machine and a test machine I have here (both
with TDM-400P's in them) have results that match this.

(Shame really, I'd like to replace the real modem on a line on the
production server with an IAXmodem process).

>>  0: 2087872259    IO-APIC-edge  timer
>>  7:          0    IO-APIC-edge  parport0
>>  8:          1    IO-APIC-edge  rtc
>>  9:          1   IO-APIC-level  acpi
>> 14:   18440124    IO-APIC-edge  ide0
>> 15:    4456445    IO-APIC-edge  libata
>> 169:    4878102   IO-APIC-level  eth0
>> 177: 2086847525   IO-APIC-level  wctdm24xxp
>> 185: 2086810653   IO-APIC-level  wct4xxp 
> 
> 
> Notice the priorities here... and that your Zaptel cards come *last*,
> after eth0, after IDE.  Each of those Zap cards are going to generate an
> interrupt once every millisecond when in use.  You can hopefully imagine
> how IDE or eth0 activity would interfere, since they have a higher
> priority than the Zap cards.
> 
The weird thing is, looking at the motherboard manual for my test
machine, The lower the Interrupt does not neccesarily mean the higher
the priority. Eg. 8 to 15 have a higher priority than 3 to 7.

On the bright side on that machine there is an IRQ -> slot allocation
system in the BIOS.

On the down side, it appears to do bugger all. (as below)

  0:         63   IO-APIC-edge      timer
  1:          2   IO-APIC-edge      i8042
  6:          5   IO-APIC-edge      floppy
  7:          0   IO-APIC-edge      parport0
  8:          1   IO-APIC-edge      rtc
  9:          0   IO-APIC-fasteoi   acpi
 12:          3   IO-APIC-edge      i8042
 14:       4744   IO-APIC-edge      ide0
 15:      11412   IO-APIC-edge      ide1
 17:        428   IO-APIC-fasteoi   eth0
 19:      40266   IO-APIC-fasteoi   ehci_hcd:usb1, uhci_hcd:usb2,
uhci_hcd:usb3, uhci_hcd:usb4, uhci_hcd:usb5
 20:          0   IO-APIC-fasteoi   VIA8237
 21:    1284151   IO-APIC-fasteoi   wctdm

I've also noticed that on the production server, the card not only has
the lowest priority but is now sharing an IRQ (probably happened last
time I saw fit to shut the machine down).

 0: 2931864860          XT-PIC  timer
 1:       1659          XT-PIC  i8042
 2:          0          XT-PIC  cascade
 3:        270          XT-PIC  uhci_hcd:usb3
 4:    3231957          XT-PIC  serial
 5:          0          XT-PIC  uhci_hcd:usb4
 6:   13146224          XT-PIC  dpti0
 7:  475736174          XT-PIC  eth0, eth1
 8:          4          XT-PIC  rtc
10:          0          XT-PIC  uhci_hcd:usb2, uhci_hcd:usb5
11: 2931432215          XT-PIC  ehci_hcd:usb1, wctdm
14:        759          XT-PIC  ide0

Guess I'll try disabling the USB controllers and moving cards round again.