[App_rpt-users] First experience with ACID app_rpt & usbradio audio popping problem.

Jacob Suter jsuter at intrastar.net
Wed Nov 18 18:56:32 UTC 2009



> -----Original Message-----
> From: app_rpt-users-bounces at qrvc.com [mailto:app_rpt-users-
> bounces at qrvc.com] On Behalf Of Steve Gladden
> Sent: Wednesday, November 18, 2009 8:58 AM
> To: Jim Duuuude
> Cc: app_rpt mailing list; sales at qrvc.com
> Subject: Re: [App_rpt-users] First experience with ACID app_rpt &
> usbradio audio popping problem.
> 
> Jim Duuuude wrote:
> > if you dont mind, I would like to ask a completely left-field
> question.
> >
> > What kind of ethernet hardware do you have on your system, and what
> kind of
> > bus controller (northbridge, etc). Back in the really old days when
> we first
> > were using Zapata Telephony cards, we found a number of drivers that
> had, well
> > lets say, some serious issues in Linux.
> >
> > Thanks for humoring me.
> >
> > JIM WB6NIL
> >
> >
> > ----------------------------------------
> >
> >> Date: Tue, 17 Nov 2009 14:27:01 -0500
> >> From: steve at michiganbroadband.com
> >> To: sales at qrvc.com
> >> CC: app_rpt-users at qrvc.com
> >> Subject: Re: [App_rpt-users] First experience with ACID app_rpt &
> usbradio audio popping problem.
> >>
> >> Stephen Rodgers wrote:
> >>
> >>> Steve Gladden wrote:
> >>>
> >>>
> >>>> Hi David.. it's not a terribly loud popping it's right with the
> normal audio
> >>>> levels
> >>>> It really sounds like 'holes' in the processing small abrupt
> dropouts of the
> >>>> stream..
> >>>> Very random in timing maybe 5-15 hits per minute when I key the
> radio with
> >>>> PL..
> >>>>
> >>>> Seems to more frequently happen on/around the CWID but still is
> happening
> >>>> very randomly.
> >>>>
> >>>> CPU utilization is ~10% while radio keyed producing PL and CWID..
> >>>> Have radio continuously keyed (no actual radio) and CDID beacon
> going every
> >>>> minute.
> >>>>
> >>>> 5-15 'dropouts' per minute.
> >>>>
> >>>> I've tried to isolate it by throwing different tasks at the
> hardware/CPU to
> >>>> see if the audio dropouts
> >>>> Would increase or not during heavy CPU utilization or maxing out
> IO on
> >>>> network hard drives etc.
> >>>>
> >>>> Checked alsa mixer to make sure there were no open turned way up
> audio
> >>>> inputs or mic monitor turned on..
> >>>> Turned down all input levels and this had no effect on the
> dropouts either.
> >>>>
> >>>> One thing I have not tried (but will not matter) is to hook a usb
> HDD to the
> >>>> usb port and give the usb controller
> >>>> Itself some activity besides the usbradio port and see if this
> impacts the
> >>>> issue.
> >>>>
> >>>> This might tend to point me back to the usb controller itself
> having an
> >>>> issue..
> >>>>
> >>>> I should also try a PCI external USB card on the motherboard and
> give it
> >>>> it's own interrupt.
> >>>>
> >>>> :-)
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>> -----Original Message-----
> >>>> From: David McGough [mailto:kb4fxc at inttek.net]
> >>>> Sent: Thursday, November 12, 2009 6:57 PM
> >>>> To: Steve Gladden
> >>>> Cc: app_rpt-users at qrvc.com
> >>>> Subject: Re: [App_rpt-users] First experience with ACID app_rpt &
> usbradio
> >>>> audio popping problem.
> >>>>
> >>>>
> >>>> Hi Steve,
> >>>>
> >>>> What exactly do you mean by "popping"?? Is it a loud POP! like a
> drum or
> >>>> is it a momentary audio drop-out or choppiness??
> >>>>
> >>>> The reason I ask about choppiness is that I've experienced this
> issue.
> >>>> But, I've never had loud POPS! ....
> >>>>
> >>>> 73, David kb4fxc
> >>>>
> >>>>
> >>>>
> >>>> On Wed, 11 Nov 2009, Steve Gladden wrote:
> >>>>
> >>>>
> >>>>
> >>>>> Short version:
> >>>>>
> >>>>> *Installed ACID
> >>>>> *Have audio popping problem with USB transmit (output) audio.
> >>>>> *I'm not surprised didn't expect it to work perfectly first
> attempt.
> >>>>> *Only tried one combinarion of hardware/cpu/motherboard so far..
> I need
> >>>>> to try other motherboards/CPUs.
> >>>>> * Tried 3 different USB devices and ports.
> >>>>> * played with moving interrupts disabling motehrboard built-on
> hardware
> >>>>>
> >>>>>
> >>>> etc.
> >>>>
> >>>>
> >>>>> * CPU runs at about 10% while USB radio is active..
> >>>>> * Loading PC heavily by running gzip -9 seti at home Lots of disk
> access
> >>>>> lots of network activity seem to have zero impact on the popping
> >>>>> frequentness.
> >>>>>
> >>>>> * I'd like to know if anyone else here has had this or similar
> problems
> >>>>> with consistent audio from the USB device (CM-108) and what they
> may
> >>>>> have done
> >>>>> to make it work better.
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>> Long Version:
> >>>>>
> >>>>> I gave it a go and went the 'easy' route just to get started..
> >>>>> I ended up trying it out on that 1.1Ghz AMD Duron CPU rack mount
> server..
> >>>>> I must say I'm extremely excited & please with this software..
> >>>>> But it would be too good to be true if it all just worked first
> try..
> >>>>> and of course would take all the 'fun'
> >>>>> out of getting it to work..
> >>>>> Ok enough small talk (haha)
> >>>>> Here's what I have going on:
> >>>>>
> >>>>> Everything works except I am getting intermittent audio popping
> in the
> >>>>> audio output of the USB sound device.
> >>>>> VERY intermittent maybe about 3-4 'pops' every minute on
> average.. 10 at
> >>>>> most sometimes.. and other times several minutes go by without a
> 'pop'.
> >>>>> It seems to mostly occur during the CW ID beacon which I have
> going
> >>>>> every minute..
> >>>>> The pops that are heard only happen when the 'transmitter' is
> active
> >>>>> sending PL or CW ID or PLAYBACK...
> >>>>> My test arrangement has "radio key" running to produce continuous
> PL and
> >>>>> occasional audio popping.
> >>>>> There is no radio actually hooked up yet.
> >>>>>
> >>>>> OK will talk about the hardware a bit.. and probably worse case
> scenario
> >>>>> here due to an 'all in one' motherboard..
> >>>>> It's a MSI 6378 'budget' Athlon board.. everything built on.
> >>>>> Has USB 1.1 *NOT 2*
> >>>>> I don't know/think this matters for a sound device.
> >>>>>
> >>>>> Here's all of the things I have tried all of which have
> absolutely no
> >>>>> effect on the intermittent popping...
> >>>>>
> >>>>> 1. Disabling everything not needed on motherboard including
> ethernet for
> >>>>> test..
> >>>>> ethernet + usb share an interrup line and there is no ability to
> >>>>> re-route this in the bios
> >>>>> so I turned off the ethernet on the motherboard for testing.
> >>>>>
> >>>>> 2. Carefully monitor CPU during audio pops running 'top' around
> 20
> >>>>> updates per second (this alone takes more CPU load than asterisk
> >>>>> /app_rpt + usb radio.
> >>>>>
> >>>>>
> >>>>> 3. On this motherboard the USB controller and ethernet share a
> PCI
> >>>>> interuupt line and you cannot change it.
> >>>>> I've tried disabling the built on ethernet and still get the
> popping..
> >>>>> I've also flood and large pinged the machine which genreates huge
> >>>>> numbers of interrups from the ethernet chip and this has no
> effect on
> >>>>> the popping..
> >>>>>
> >>>>> 4. Tried other USB fobs with same chipset.
> >>>>> Created various types of heavy system activity to see if it has
> any
> >>>>> impact on the popping heavy disk use hevy network use and heavy
> vga use
> >>>>> (text mode)
> >>>>> moving interrupts (changing them) on the motherboard.. getting
> usb
> >>>>> controller onto a different interuupt (ethernet ends up on same).
> >>>>>
> >>>>> 5. Measured and scoped 5V output on USB to be sure 'popping'
> sound is
> >>>>> not coming from 5V power supply.
> >>>>>
> >>>>> 6. Am really looking to hear what some others experience has been
> with
> >>>>> this..
> >>>>> what works and what does not?
> >>>>> The popping very much sounds like an interrupt issue or some kind
> of
> >>>>> issue where the task of sending and audio stream is completely
> dropped
> >>>>> for something else
> >>>>> and then resumed leaving lots of holes heard as pops in the
> output stream.
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>> This is reported occasionally, but I've never experienced it.
> >>>
> >>> Given what you've tried already, I'd try a different motherboard.
> >>>
> >>> Also, remove any usb hobs if you are using one.
> >>>
> >>>
> >>> Steve
> >>> WA6ZFT
> >>>
> >>>
> >>>
> >>>
> >> Hello David... I *may* also be on to something here as I've been
> able to
> >> also determine that the audio pops are occuring ALWAYS
> >> While app_rpt is doing it's statpost routine! updating stats via the
> web.
> >>
> >> I set te statpost address to something local on the LAN for now just
> for
> >> testing but I get the same audio pops whether just on the
> >> LAN or if it's statposting out to the internet.
> >>
> >> The popping definitely happening at the time that app_rpt is sending
> >> HTTP out..
> >> The popping never happens during other access to-from the ethernet
> or
> >> during IAX interchanges between asterisk and the world..
> >> Seems to be only when app_rpt is stat posting...
> >> Dave I think you are certainl correct about the issue being within
> app_rpt.
> >> I'm sure the stat posting is not the only issue but I can duplicate
> the
> >> problem 100% by seeing the popping every time app_rpt
> >> sends out HTTP. :-)
> >>
> >> You may have already found that app_rpt does the 'droppouts' with a
> ton
> >> of other activities... not just stat posting like I am currently
> >> pointing out...
> >>
> >> Might be a start to something though... since it's duplicatable
> here. :-)
> >>
> >> Note: I've not figured out how to manually make it statpost.. I just
> >> turend up the debug to 7 and waited for it to say it was statposting
> >> also looking at the ethernet and see the HTTP packets go out at same
> >> time dropous are ocurring.
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >> --
> >> This message has been scanned for viruses and
> >> dangerous content by MailScanner, and is
> >> believed to be clean.
> >>
> >> _______________________________________________
> >> App_rpt-users mailing list
> >> App_rpt-users at qrvc.com
> >> http://qrvc.com/mailman/listinfo/app_rpt-users
> >>
> >
> >
> I'm on test machine #4 now this one is a P3 @450Mhz  on an Asus P2-99
> Motherboard.. no built on video audio or ethernet..
> A bit of a slower CPU on this one the audio dropouts are about the same
> (just as bad no worse) Turning off the stat post
> by commenting out the two lines makes a HUGE difference for the better
> but still not perfect as there is still some dropouts..
> This is totally stock off the ACID install after all updates & setup.
> 
> I still (badly) need to try David's suggested source and re-compile
> fixes and see what I get.
> I've certainly found that the stat post part of app_rpt is really
> making
> the problem show up when it is active.
> Besides needing to apply & try David's fixes I am still at the same
> time
> trying this on a variety of different hardware..
> So far ACID out of the box has had the same issue of 4 different
> systems.
> 
> On this last attempt with a P2-99 I've gotten away from the VIA
> chipsets
> and pretty much all of the on motherboard problem/frustration causers.
> This Motherboard uses Intel NB and SB.. A copy of the manual for this
> one is at: http://stuff.michiganbroadband.com/p2-99.pdf


You're currently describing why I don't use Asterisk for my PBX - it seems
to desire an outrageous amount of dedicated resources to make work
consistently.  I find FreeSwitch seems to work 99% better in these
situations, but FreeSwitch's repeater control module (fs_rpt) is still
incomplete and theres no Echolink or IRLP linking options (yet)

>From my own tests I can say Asterisk isn't as much CPU hungry as it is
"consistent performance hungry".  Your old P3 is likely fast enough to
handle the job, but when things like disk I/O occur (IDE and SATA drives
*LOVE* 'eating' your machine's performance up during I/O) it just can't keep
up for a few milliseconds, and asterisk doesn't recover well from the
situation.

People tend to throw a lot of CPU at it, because CPU is cheap and easy, and
end up having the same problems.  I'm fairly certain $25 worth of surplus
SCSI controller, cable, and disk off ebay would likely cure the largest
problems you're seeing.

Also, while you're Ebaying, treat yourself to a nice Intel 10/100 adapter.
I buy them surplus by the 10 pack, myself.  Junk Ethernet adapters (Realtek,
VIA, etc) are a performance-eater under any circumstance.

Good Luck!

JS






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