Re: [Jack-Devel] ardour3, netjack, bandwidth, xruns

On 01/03/2014 06:13 AM, Stéphane Letz wrote:
> Try to change the "mtu" value on slave side, using "jumbo" frames on GB network, like
>
> jackd -d net -M  9000

If I need to ...

This problem was a difficult one to diagnose. As it turns out, I think 
I've pinpointed it to the combination usage of PulseAudio and google-chrome.

I have been running the PulseAudio JACK sink/source from day one without 
problems but very recently installed google-chrome. The only time I get 
any kind of xruns is when google-chrome is open and as it turns out, 
quite exaggerated (as reported below) with net manager.

After a few trial and errors, I realized that closing chrome quieted the 
xruns. So I have 4 midi-out ports (16 channels each) connected over the 
network returning 48 audio channels. I haven't exercised it completely, 
but connection is clean without xruns... so far so good.

David


>
> Stéphane
>
> Le 1 janv. 2014 à 17:42, David Santamauro <[hidden]> a écrit :
>
>>
>> Hi,
>>
>> Happy new year ... if this isn't the appropriate list, direct to the
>> right one, thanks.
>>
>> I've started creating my orchestral template using ardour3 (on the
>> master) and a slave. When I reach a certain number of tracks the xruns
>> start piling up.
>>
>> Master message(s):
>> Wed Jan  1 07:15:08 2014: NetMaster : overloaded, skipping receive from
>> 'nslave01'
>>
>> ... does this mean the master is overloaded?
>>
>> The specs:
>>   - master is an 8-core/16GB RAM
>>   - slave is 4-core/16GB RAM
>>
>> Goal is to use windows orchestral VSTi(s) whose required 'dongle' is on a windows machine.
>>
>>   ardour3:midi-track-1 => slave:midi-input-1
>>   slave:audio-out-1    => ardour3:audio-track-in-1
>>   slave:audio-out-2    => ardour3:audio-track-in-2
>>
>> Pretty simple, actually, but I'd like 48 channels of audio to come back from the slave.
>>
>> Both have Gb network interfaces and both are connected to a Gb switch.
>>
>> ardour3 does take CPU slices but the master load avg is ~ 85% idle and
>> DSP load < 20%.
>>
>> Viewing network traffic using iptraf, I see total usage in the 45Mb/s
>> (4% utilization) range for both master and slave -- clearly room to
>> spare so I'm assuming there is some other bottleneck somewhere.
>>
>> I guess the questions are:
>>
>>   - are there hard limits on the number of tracks that can be used when
>> using using jack over the network?
>>
>>   - Is there a formula to figure out this out, e.g., is there a
>> relationship between the size of the jack graph and data per cycle?
>>
>>   - Are there settings (network or for jack_load netmanager) that would
>> help this situation?
>>
>> Both master and slave jackd versions are the same:
>>
>> $ jackd -V
>> jackdmp 1.9.9.5
>>
>> I've read this [1] and it appears there are two modes: sync and async.
>> I'll try toggling this and see what happens.
>>
>> ... but any other help would be appreciated.
>>
>> David
>>
>> [1] http://trac.jackaudio.org/wiki/WalkThrough/User/NetJack2
>>
>>
>> 
>> Jack-Devel mailing list
>> [hidden]
>> http://lists.jackaudio.org/listinfo.cgi/jack-devel-jackaudio.org
>

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