Writeagan to coll memory impact

Max 7.0.3
OS X 10.10.3
As I troubleshoot this:
https://cycling74.com/forums/long-term-changes-in-audio-roundtrip-latency/
I am noticing a noticeable memory impact when using the "writeagain" message to coll.
Running the pasted patch leads to an ever increasing amount of memory committed to Max in the Activity Monitor.
Can anyone reproduce this? is this expected?
{
    "version" : "Version 7.0.3 (37355d2) (64-bit mac)",
    "platform" : "mac",
    "arch" : "x64",
    "osversion" : "Mac OS X Version 10.10.3 x86_64",
    "samplerate" : 44100,
    "iovs" : 2048,
    "sigvs" : 2048,
    "scheduler_in_audio_interrupt" : "off",
    "audio_drivername" : "Core Audio",
    "audio_driver_subname" : "",
    "license" : "permanent full",
    "machine_id" : "Alice",
    "eventinterval" : 2,
    "overdrive" : "off",
    "mixerparallel" : "on",
    "mixercrossfade" : 0,
    "mixerlatency" : 30.0,
    "mixerramptime" : 10.0,
    "videoengine" : "avf",