[Ardour-Dev] Recording may channels at once

[Scott Bahling]

On Thu, 2008-07-10 at 16:41 +0200, Kjetil S. Matheussen wrote:
> On Thu, 10 Jul 2008, Kjetil S. Matheussen wrote:
> 
> > 
> > 
> > On Wed, 9 Jul 2008, Sampo Savolainen wrote:
> > 
> > > On Fri, 2008-07-04 at 13:05 +0200, Kjetil S. Matheussen wrote:
> > >> I just did some benchmarks recording 128 channels (16 X 8):
> > >>
> > >> Recording times before failing, without waveforms while recording:
> > >> 55s
> > >> 19s
> > >> 8s
> > >>
> > >> Recording times before failing, with waveforms while recording:
> > >> 16s
> > >> 24s
> > >> 18s
> > >>
> > >> I run some other programs in the background accessing the
> > >> disk, so that could explain the large variations.
> > >
> > > Sounds bad though. Can you try the same test so that you use the same
> > > background load. Preferably no extra load.
> > >
> > 
> > It's a bit more consistent now. Below are results without any other
> > programs running, exept emacs, pine, jack, konsole and qjackctl.
> > I had 1GB free of memory, and had 5.94s long buffer for ardour.
> > Total CPU usage was, according to "top", about 20% while recording,
> > and Jack reported about 12% dsp cpu usage.
> > 
> > 09s
> > 13s
> > 12s
> > 12s
> > 12s
> > 19s
> > 
> > The next time I tried, after the result with 19 seconds, something 
> > interesting happened. Suddenly, after a few seconds, I get a bunch of 
> > errors which says something like this:
> > 
> >    "can not write peak file, too many open files",
> > 
> > and when I press the stop button, ardour crashes.
> > 
> > I would think this is an OS limitation (although one not very gracefully
> > handled by Ardour), but anyway, if ardour writes peak files while 
> > recording, then it's not that strange that jack_capture performs so much 
> > better.
> > 
> > I guess I got the error because this was the 7th recording, with
> > 128 peak files, yielding about 128*7 files.
> > This is how I worked:
> > 
> > 1. Record.
> > 2. Write down how many seconds of sound recorded.
> > 3. Undo Capture
> > 4. Goto 1.
> > 
> > Why isn't the older peak files closed and deleted?
> > 
> > kjetil at ttleush ~/longrecording/peaks $ ls -la |wc
> >      874    8730   57091
> > kjetil at ttleush ~/longrecording/peaks $
> > 
> > 
> 
> Oh, and the audio files weren't deleted either between each
> capture:

If you want the audio files deleted, use "Remove Last Capture" for step
3 instead.

-Scott