[PD] Save RAM memory usage ?

Solen Music solenpuredata at googlemail.com
Thu Jul 24 01:39:18 CEST 2008

I'm looking for a way to shrink the RAM usage in my live patch.

I'm currently running a patch for live usage which has 14 x 100 stereo
audio arrays. and 14 x 20sec variable delay lines. there's also 3 vst
plugins (compressor, limiter and tape style delay). the GUI isn't too
busy, there aren't any vu's and the arrays and lots of stuff are
hidden in subpatches.

it is basically a 7 stereo channel (hence 14 x 100, 14 mono pairs x
100 clips long in timeline) ableton live-esqe system but with a delay
line on each channel (i need different delay times each channel, hence
no send setup).

I have initialised all arrays to 6 samples (which i suppose i should
change to 1 or 0 samples if possible). So that they take up the
minumum amount of RAM when not in use (correct me if i'm wrong). i
have a loop programmed that loads the audio files into the arrays and
resizes the ones in use. they are 16 bit stereo files

The most amount of arrays I've tried to load into the patch is 588 (42
x 14) which have been roughly 15secs long and i'm running at 44.1khz.
this has lead to my RAM overloading and pd shutting locking and

I changed the 4 of the channels to mono and got away with it. but pd
still used up nearly all of my 2gb of ram. (i've recently bought more)

is there anything i can do to save on RAM??

also how can i calculate roughly how much RAM that pd will need per
second of audio array/delay line etc.??

and are there any other factors that are RAM draining (exc GUI)??

Thanks in advance, this list has been more than helpful to me in the
past but apologies for lack of brevity this time!

More information about the Pd-list mailing list