[PD] pd~ fifo latency

Miller Puckette msp at ucsd.edu
Mon Jan 27 19:12:41 CET 2014


I just tried this (on Linux) -- I get a delay of 64 samples with -fifo 1
(as I was hoping for), but Pd hangs if I start a pd~ subprocess with -fifo 0.

(I think it's reasonable to enforce a minimum fifo of 1 block since 0 block
delay woud make pd~ less efficient than simply putting everything in one
process :)

Anyhow, what OS are you on?  It seems that, on your OS, the fifo is magically
being decreased by 1, so that you're getting 4 by default (should be 5).
If you speify 2 under these conditions you should get the minimum possible:
64-sample (1 block) delay.

thanks
Miller

On Mon, Jan 27, 2014 at 07:51:00PM -0500, puredata at 11h11.com wrote:
> hi all,
> 
> in [pd~] documentation:
> -fifo <n> sets round-trip delay in blocks
> 
> when trying to use -fifo 0 or -fifo 1 (i want the lowest delay
> possible) = pd hangs. when not specifying -fifo i get 256 samples of
> delay (adding 5ms to my 13ms round-trip latency).
> 
> how to have just 1 sample delay with [pd~]?
> 
> i short video showing -fifo 20 delay:
> https://dl.dropboxusercontent.com/u/1455235/pdlatency.webm
> 
> _______________________________________________
> Pd-list at iem.at mailing list
> UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list



More information about the Pd-list mailing list