[PD] problem using [udpsend] from iemnet (or mrpeach) in a sub-process (with [pd~])

Jack jack at rybn.org
Fri Aug 20 23:54:31 CEST 2010

Hello Roman,

Le vendredi 20 août 2010 à 23:29 +0200, Roman Haefeli a écrit :
> On Fri, 2010-08-20 at 16:36 +0200, Jack wrote:
> > Hello Mathieu,
> > 
> > I have already do that with [packOSC]/[unpackOSC] and
> > [udpsend]/[udpreceive], it is slow too.
> > I need to send 20000 lists of 3 floats (id, pos x, pos y) each frame (50
> > fps) from one process to other.
> > Thanx.
> > ++
> It seems to me as you were creating a lot of overhead for tranmitting
> only 3 floats. First there is the OSC overhead per message, then each
> OSC message is sent over UDP, while adding some datagram overhead.
> By sending 20'000 or even 60'000 floats per message, you could
> drastically reduce the OSC and UDP protocol overhead. Don't know if this
> is the real reason for being so slow, but I'd try to reformat your
> messages. Also, this would probably mean using less computing power for
> creating all those messages and packets.
In fact, i have tried one more time with only [pd~] and [stdout] and it
seems to be faster than [pd~] and [udpsend]/[udpreceive]. But Pd freeze
if i send a lot of data to [pd~] :/
One remark : I am not sending 20000 or 60000 floats per message but
20000 messages of 3 floats every frame (near every 20 ms).
The problem seems to be the transfert of the packets not the creation
off the messages (they are created by [msd2D] with only one message).


> Roman

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