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

[Artifex Maximus]

Hello,

# cat /proc/interrupts
           CPU0
  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
NMI:          0
LOC: 2087921792
ERR:          0
MIS:          0

zttest is often on 99.975586% with final result:
--- Results after 67 passes ---
Best: 99.987793 -- Worst: 99.951172 -- Average: 99.973764

Where should I find good web pages for tuning? I had found this and using now:
setpci -v -s 04:06.0 latency_timer=ff
setpci -v -s 04:08.0 latency_timer=ff

As I remember it's give higher priority for Digium cards. The machine
is an IBM eServer x206 with P4 2.66 GHz processor.

bye,
Zsolt

On 9/23/06, Ma Zhiyong <zhiyong.m at gmail.com> wrote:
> zttest don't disturb your other active calls. when you have 10-20
> calls maybe got a better score.
> also cat /proc/interrupt and 'lspci -vb' to find any IRQ interrupt on
> your system.
>
> 2006/9/22, Artifex Maximus <artifexor at gmail.com>:
> > Hello,
> >
> > On 9/21/06, Lee Howard <faxguy at howardsilvan.com> wrote:
> > > Artifex Maximus wrote:
> > >
> > > > Everything is fine when caller use ECM but when ECM isn't in use I
> > > > often got unusable incoming faxes (much often that it should be). But
> > > > when I switch back to fax machine that receive faxes perfectly (at
> > > > least no visible error).
> > > The fax machine itself uses ECM, undoubtedly.
> > That's unfortunately not the case. The remote doesn't asks for ECM so
> > that's disabled or missing on that machine. In this situation fax
> > machine is produce better output and I don't know why. Might a better
> > DSP algo?
> >
> > > If callers that have
> > > quality problems with IAXmodem+HylaFAX don't have problems with the fax
> > > machine, then that strongly indicates that something is wrong with your
> > > Asterisk setup... corrupting the audio.  Usually this is due to resource
> > > constriction of the Zap device, zttest scores less than 99.98% is
> > > indicative of that situation.
> > I don't find any info that zttest is destructive or not on an active
> > system. I mean that currently active calls are disturbed or not while
> > zttest running. I can't stop system now. I look into zttest source and
> > find that zttest is using /dev/zap/pseudo but I don't know this
> > 'pseudo' channel is related to any 'real' channel or not.
> >
> > > > Where should be the problem? Is there any solution for improving
> > > > quality? Any tuning in Asterisk or Hylafax? As I see some people use
> > > > slinear for iaxmodem and some user use alaw. Which is better?
> > > There is no functional difference between using uLaw, alaw, or
> > > slinear... except that using slinear reduces the need for conversion...
> > > and thus possibly lessens CPU usage very slightly.
> > I see. I leave it on slinear.
> >
> > bye,
> > Zsolt