Ardour defaults to half the frames/period of Jack (9.11)

[mikeyouare]

NOTE: APPLIES TO Puredyne 9.11

Even with Jack operating perfectly, opening a project in Ardour results in Ardour defaulting to half the "Latency" (frames/period) value that Jack is set at. This always produces XRUNS for me.

An easy work-around is changing Ardour's latency value (Jack-->Latency-->[value]) to match Jack's frame/period or greater. This ALWAYS prevents XRUNS from Ardour (aside from some Ardour/LADSPA-specific bugs).

As a side note, that this problem does not exist on Ubuntu Studio 9.10 which also has Ardour 2.8.2, so this is why I consider it a Puredyne-specific bug.

[Aymeric Mansoux (aymeric)]

Does the same happen with one of the more recent alpha 10.10 versions of Puredyne?

[mikeyouare (mikeyouare)]

Great work. Very exciting! I'm posting this using live/failsafe puredyne-1010-gazpacho-DVD-i386-alpha4.iso

This sums up my whole experience:

1. Would only boot failsafe
2. Booted failsafe and saw that qjackctl worked at 2.9ms with xruns every 30 sec or so (not bad for Live??)
3. Installed on HDD partition (with "download updates..." and "mp3" boxes checked) to see if performance improved. Unfortunately, installer crashed near the end at "ready when you are."
4. Booted from new broken partition using Super GRUB2 and attempted RT audio...many XRUNS as if Audio group permissions had not been properly set up. Sure enough, I still had the "lintian" username that is the Live default, and not my own username...couldn't become root user, so no further updates possible. I blame the installer crash--bad install.
5. Booted again to failsafe on live DVD and installed Ardour 2.8.11 from Synaptic Package Manager
6. Running qjackctl at 2.9ms, Ardour defaulted to 1.5ms as it did in Puredyne 9.11 <-----SAME BEHAVIOR DESCRIBED ABOVE!!!!!!!!!

Other unrelated things:
In 9.11, Qsynth/Fluidsynth worked nicely with Rosegarden (also as FluidsynthDSSI within Rosegarden), and in 10.10 Alpha4, all I hear is distorted white noise on any note played. Puredyne needs to be able to do Soundfonts like it used to!! Finally, I think Ingen is one of the most incredible programs in the works out there, and if it's not included with Puredyne I will probably try it from FalkTX's PPA.

Otherwise, this is GREAT, GREAT work. It's definitely going in the right direction: simple improvement, and not overbloat.

Do you know if any of the other ISO files are more stable for HDD install than DVD-i386-alpha4.iso??

[mikeyouare (mikeyouare)]

Upon further investigation I found that in Ardour's Jack latency menu, the "frames/period" DO in fact match up with the number in qjackctl. What showed a confusing half-value was Ardour's "output latency" display (always half the milliseconds shown in Jack). The XRUNS I saw were probably just due to Ardour requiring twice the latency of other jack programs. So, to me, this behavior is actually not a bug. Nothing to fix.

However, there was another Ardour latency-related bug in 9.11 that was fixed in Ardour 2.8.8 (http://ardour.org/node/3384). So, as long as Gazpacho uses at least 2.8.8, should be good.

[mikeyouare (mikeyouare)]

Whoever reported this bug is an idiot!!! :D

As I said in the status change above...

Upon further investigation I found that in Ardour's Jack latency menu, the "frames/period" DO in fact match up with the number in qjackctl. What showed a confusing half-value was Ardour's "output latency" display (always half the milliseconds shown in Jack). The XRUNS I saw were probably just due to Ardour requiring twice the latency of other jack programs. So, to me, this behavior is actually not a bug. Nothing to fix.

However, there was another Ardour latency-related bug in 9.11 that was fixed in Ardour 2.8.8
(http://ardour.org/node/3384). So, as long as Gazpacho uses at least 2.8.8, should be good.

FYI--Ardour 3.0 alpha contains MIDI related features...maybe if Gazpacho takes long enough, it can be included. Though I don't know if it contains the same cool DSSI stuff as Rosegarden.