[ardour-users] Re: [ardour-dev] Strange Issue WIth Automation in ardour-0.9_beta11

[David R. Bergstein]

David R. Bergstein wrote:
> Paul Davis wrote:
>>
>>
>> Please notice the "[speed=8]" line. You were apparently
>> fast-forwarding when this happened. An 8-fold speed up is quite a lot,
>> especially if you have only 7200 RPM disks (or worse). If you weren't
>> ffwd-ing, we have some other bug to solve, because ardour thinks you 
>> were.
> 
> 
> Paul,
> 
> Thanks for pointing that out.  I was "playing" a bit with fast forward 
> the same day well after the original errors were written to the log 
> file.  Here is a more typical set of events from 23Feb04 with 
> ardour-0.9_beta11:
> 
> transport Starting, sync poll of 1 clients for 2.000000 secs
> transport Rolling, 2.000000 sec left for poll
> load = 35.2009 max usecs: 4043.000, spare = 6623.000
> load = 36.4079 max usecs: 4012.000, spare = 6654.000
> load = 37.3161 max usecs: 4077.000, spare = 6589.000
> load = 38.3140 max usecs: 4193.000, spare = 6473.000
> load = 38.1988 max usecs: 4062.000, spare = 6604.000
> load = 37.9818 max usecs: 4028.000, spare = 6638.000
> DiskStream Vocals:0: playback underrun (called with 512 samples but only 
> 0 available; other half: 0) [speed=1]
> load = 47.0099 max usecs: 5977.000, spare = 4689.000
> transport command: STOP
> transport Stopped


Reported in mantis as id 0000280:
http://ardour.org/mantis/bug_view_page.php?bug_id=0000280

> 
>>
>>
>>> Another, possibly unrelated, dilemma is an issue I have been 
>>> encountering when running latencies (with or without automation) at 
>>> or below 3 ms latency (i.e., p=256, n=2 @ 48KHz sampling rate) when 
>>> running a 2.4 kernel. In this case, the ardour log window displays a 
>>> bizarre error message saying something about a MIDI memory pool error 
>>> and to please compile with larger size.  When I run a 2.6 kernel, 
>>> this error does not seem to occur. 
>>
>>
>>
>> i am sorry to say that this is a long standing problem that we have
>> never tracked down. i hope we can solve it before the release of 1.0.
>> please make sure its registered with mantis (ardour.org/mantis)
> 
> 
> No problem, I can do that . . .
> 

Reported in mantis as id 0000281:
http://ardour.org/mantis/bug_view_page.php?bug_id=0000281

>>> sessions), however, the disk stream errors persist whenever 
>>> automation is enabled and my system latency is set any lower than 
>>> 11ms (p=1024,n=2 at 48KHz).
>>>
>>> My current workaround is to run the gentoo development kernel 
>>> 2.6.3-r1, and use low latencies as low as 3 ms for recording or 
>>> non-automated mixdowns, and a setting of 11ms latency or greater if I 
>>> am mixing down with automnation.
>>
>>
>>
>> how many tracks are you using? a PIII-450 is not a particularly speed
>> machine, and it *is* possible that automation is bogging you
>> down. however, the problems you mentioned above are not related to
>> automation in any direct sense.
>>
> 
> Although my hdsp can handle up to 24 channels of ADAT I only am 
> currently using a maximum of 8.  Most of the mixes I have so far have 
> between 5 and 7 tracks.  IF you take a look at the spare time jackd is 
> reporting in the extract pasted above, there seems to be enough headroom 
> in the CPU for the work I am doing.  What is interesting is the fact 
> that automation in one of the earlier betas (either ardour-0.9_beta9 or 
> ardour-0.9_beta10) seemed to work without these issues.
> 
> Thanks again for all the fine work you and the ardour development team 
> are doing.
> 
> Regards,
> 
> - David
> 


-- 

David R. Bergstein
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