[PD] finding the cause of clicks when using sssad WAS: saving state of a patch

Phil Stone pkstone at ucdavis.edu
Wed Jul 23 16:54:03 CEST 2008

Hi Hans,

I don't think this is anything to do with sssad, really.  It is due to 
Pd's lack of a threaded file loader/saver.  The way I understand it (and 
this is borne out by my experience), if a file operation cannot complete 
within one dsp cycle, the next dsp cycle is delayed until after the file 
operation completes, thus causing dropouts.

Ram disks help (with files that are not too big) because they speed up 
the file operation to the point where it can happen safely within one 
dsp period.

This has been discussed many times on the list without any hope of 
change, but it would be so great for Pd's use in live performance if 
some tasks could be relegated to a background thread.  Or, to put it 
another way, the dsp engine should have highest priority at all times.

Phil Stone

Hans-Christoph Steiner wrote:
> On Jul 22, 2008, at 2:31 AM, Enrique Erne wrote:
>> Phil Stone wrote:
>>> Hi Atte,
>>> Now that you're on your way with sssad, there's a nice trick you should
>>> know.  If you find that loading a preset causes dropouts, consider 
>>> using
>>> a ram disk to hold your presets during performance.  This solved all my
>>> dropout problems, and it's easy to do (I can post a script for OS X if
>>> anyone wants it).
> The ramdisk thing is definitely handy, I just hope that sssad can be 
> tweaked to work without causing dropouts.  Any ideas what the cause is?
> .hc
> ---------------------------------------------------------------------------- 
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