On Jun 25, 2017, at 12:00 PM, pd-list-request@lists.iem.at wrote:

From: Miller Puckette <msp@ucsd.edu>

Subject: Re: [PD] MIDI timing FIFO overflowed receiving sysex

Date: June 25, 2017 at 1:37:21 AM GMT+2

To: mario buoninfante <mario.buoninfante@gmail.com>

Cc: pd-list@lists.iem.at

If you don't mind recompiling Pd, you can control the MIDI queue size
by editing this line in s_midi.c:

#define MIDIQSIZE 1024

I think it has to be a power of 2.  You could make it 0x100000, for instance
(a million-ish).

To easily recompile Pd on a Mac, install the developer package (compiler
chain which I think is now called Xcode), open a shell, Cd to 
Pd-x.app/Contents/Resources/src, edit s_midi.c, and type "make".

cheers
Miller