[PD] block~ and effective blocksize

Miller Puckette mpuckett at man104-1.ucsd.edu
Sat Apr 27 00:25:49 CEST 2002

Well, you've hit on a major weakness of Pd's scheduler.  The block size can
go all the way down to 1 (check it out using print~ for example)... BUT ...
control computations only occur at intervals of 64 samples.  So bang~, which
sets a delay so as to schedule a (message/control time) bang, might schedule it
64 times in a 64-sample period, but at the end of the show, only one of
the 64 comes out.

I wish I knew a better way to interleave control and DSP scheduling, but
so far, the best I can come up with is to have the grain at which control
passes back and forth be a global quantity.  In Pd it's arbitrarily set to


On Fri, Apr 26, 2002 at 07:24:25PM +0200, intent wrote:
> Hi,
> Can we go below a blocksize of 64 ?
> I have been trying with pd0.34-4 and 0.34-2-updown without success.
> Basiclly i count the number of bang from a bang~ object during 1 second and 
> still get 750, which is well 48000/64, but even with blocksize of 32 and less.
> Any hints ?
> Linium

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