Eric Lyon

I am seeing high CPU usage from a very simple gen~ codebox program that reads two buffers and interpolates and writes their contents into a third buffer. Code is below, followed by system report. When running on a 3.2 GHz dual-core Mac, this patch takes about 15% of CPU. When the gen~ subpatch is removed, CPU usage drops to zero. Any idea why this is so expensive?

comment

flonum

message

scale~

cycle~

waveform~

buffer~

gen~

codebox

    "version" : "Version 7.3.5 (be88c5a) (64-bit mac)",

    "osversion" : "Mac OS X Version 10.13.6 x86_64",

    "scheduler_in_audio_interrupt" : "on",

    "audio_drivername" : "Core Audio",

    "machine_id" : "6fd8012aec42ed32cd8083dc0cce0c0c",

        "Max" :         {

        "MSP" :         {

        "Jitter" :         {

            "name" : "Jitter",

        "Max for Live" :         {

            "name" : "Max for Live",

        "Gen" :         {

            "version" : "1.0.1",

        "max-mxj" :         {

            "author" : "Cycling '74",

            "description" : "Max Java Support",

            "displayname" : "",

            "extensible" : 0,

            "homepatcher" : "",

            "max_version_max" : "none",

            "max_version_min" : "7.2.5",

            "name" : "max-mxj",

            "os" :             {

                "macintosh" :                 {

                    "platform" : [ "ia32", "x64" ],

                    "min_version" : "none"

                "windows" :                 {

            "version" : "7.2.5",

        "MaxDefaultContent" :         {

            "name" : "MaxDefaultContent",

        "MaxIntroLessons" :         {

            "name" : "MaxIntroLessons",

        "Mira" :         {

            "description" : "Mira automatically connects to Max and mirrors your interface. This Mira Package update (version 1.2.0) is required for use of the Miraweb Package.",

            "max_version_min" : "7.1",

            "version" : "1.2.1",

        "VIDDLL" :         {

            "author" : "Rob Ramirez",

            "description" : "The VIDDLL package installs a Jitter video engine adapter for jit.movie, allowing file playback via the VIDDLL library.\n\nVIDDLL is an interface and set of utilities for cross platform, high performance, random access video playback. VIDDLL is copyright Paul Bamborough and Julian Storer. \n\nThis software uses code of FFmpeg - 

http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html

 - and its source can be downloaded here - 

https://cycling74.s3.amazonaws.com/download/ffmpeg-3.0.2.tar.gz

            "max_version_min" : "7.3.4",

            "name" : "VIDDLL",

                    "min_version" : "10.9.x"

                    "min_version" : "7"

            "version" : "1.1.4",

        "Video and Graphics" :         {

            "description" : "Video and Graphics programming tutorials",

            "max_version_min" : "7.2",

            "name" : "Video and Graphics",

            "version" : "7.2.0",

        "Vizzie" :         {

            "description" : "With VIZZIE, you just grab a few simple modules, connect them together and almost instantly have a VJ rig or interactive video work, complete with real-time effects.",

            "extensible" : 1,

            "max_version_min" : "6.1.10",

            "name" : "Vizzie",

            "version" : "1.0.2",

http://cycling74.com/2010/11/19/introducing-vizzie/

        "Lyon Package" :         {

            "name" : "Lyon Package",

            "author" : "Benjamin D. Smith",

            "description" : "A toolbox of unsupervised machine learning algorithms implemented in Max to support on-line learning, and real-time interactive music and video, aimed at the non-expert computer artist.",

            "homepatcher" : "

            "max_version_min" : "none",

            "version" : "1.0.0",

        "Dualities Package" :         {

            "name" : "Dualities Package",

        "FFTease 3.0 Package" :         {

            "name" : "FFTease 3.0 Package",

        "HoaLibrary-Mac-v2.2" :         {

            "name" : "HoaLibrary-Mac-v2.2",

        "ICST_ambisonics_2_3_1" :         {

            "name" : "ICST_ambisonics_2_3_1",

        "Jamoma" :         {

            "name" : "Jamoma",

        "Lyon" :         {

        "LyonPotpourri 3.0 Package" :         {

            "name" : "LyonPotpourri 3.0 Package",

            "version" : "0.1.3",

https://github.com/JulesFrancoise/myo-for-max

        "Max-SDK" :         {

            "description" : "Max Software Development Kit",

            "name" : "Max-SDK",

                    "min_version" : "10.7.x"

            "version" : "7.1.0",

        "MIAP_for_Max" :         {

            "name" : "MIAP_for_Max",

        "myo-for-max-0.1.3" :         {

            "name" : "myo-for-max-0.1.3",

I am seeing  high CPU usage from a very simple gen~ codebox program that reads two buffers and interpolates and writes their contents into a third buffer.  Code is below, followed by system report.  When running on a  3.2 GHz dual-core Mac, this patch takes about 15% of CPU. When the gen~ subpatch is removed, CPU usage drops to zero.  Any idea why this is so expensive? 

{
	"version" : "Version 7.3.5 (be88c5a) (64-bit mac)",
	"platform" : "mac",
	"arch" : "x64",
	"osversion" : "Mac OS X Version 10.13.6 x86_64",
	"samplerate" : 48000,
	"iovs" : 512,
	"sigvs" : 128,
	"scheduler_in_audio_interrupt" : "on",
	"audio_drivername" : "Core Audio",
	"audio_driver_subname" : "",
	"license" : "permanent full",
	"machine_id" : "6fd8012aec42ed32cd8083dc0cce0c0c",
	"eventinterval" : 2,
	"overdrive" : "off",
	"mixerparallel" : "off",
	"mixercrossfade" : 0,
	"mixerlatency" : 30.0,
	"mixerramptime" : 10.0,
	"videoengine" : "avf",
	"packages" : 	{
		"Max" : 		{
			"name" : "Max",
			"domain" : 1,
			"domains" : 1
		}
,
		"MSP" : 		{
			"name" : "MSP",
			"domain" : 1,
			"domains" : 1
		}
,
		"Jitter" : 		{
			"name" : "Jitter",
			"domain" : 1,
			"domains" : 1
		}
,
		"Max for Live" : 		{
			"name" : "Max for Live",
			"domain" : 1,
			"domains" : 1
		}
,
		"Gen" : 		{
			"name" : "Gen",
			"domain" : 1,
			"domains" : 1
		}
,
		"BEAP" : 		{
			"author" : "Matthew Davidson, Peter McCulloch",
			"description" : "BEAP (Berklee Electro Acoustic Pedagogy) Modular is a synthesis pedagogical tool.",
			"displayname" : "",
			"extends" : "",
			"extensible" : 1,
			"homepatcher" : "",
			"max_version_max" : "none",
			"max_version_min" : "6.1.10",
			"name" : "BEAP",
			"os" : 			{
				"macintosh" : 				{
					"platform" : [ "ia32", "x64" ],
					"min_version" : "none"
				}
,
				"windows" : 				{
					"platform" : [ "ia32", "x64" ],
					"min_version" : "none"
				}

			}
,
			"version" : "1.0.1",
			"website" : "https://github.com/stretta/BEAP/wiki",
			"domain" : 32,
			"domains" : 32
		}
,
		"max-mxj" : 		{
			"author" : "Cycling '74",
			"description" : "Max Java Support",
			"displayname" : "",
			"extends" : "",
			"extensible" : 0,
			"homepatcher" : "",
			"max_version_max" : "none",
			"max_version_min" : "7.2.5",
			"name" : "max-mxj",
			"os" : 			{
				"macintosh" : 				{
					"platform" : [ "ia32", "x64" ],
					"min_version" : "none"
				}
,
				"windows" : 				{
					"platform" : [ "ia32", "x64" ],
					"min_version" : "none"
				}

			}
,
			"version" : "7.2.5",
			"website" : "http://www.cycling74.com",
			"domain" : 32,
			"domains" : 32
		}
,
		"MaxDefaultContent" : 		{
			"name" : "MaxDefaultContent",
			"domain" : 32,
			"domains" : 32
		}
,
		"MaxIntroLessons" : 		{
			"name" : "MaxIntroLessons",
			"domain" : 32,
			"domains" : 32
		}
,
		"Mira" : 		{
			"author" : "Cycling '74",
			"description" : "Mira automatically connects to Max and mirrors your interface. This Mira Package update (version 1.2.0) is required for use of the Miraweb Package.",
			"displayname" : "",
			"extends" : "",
			"extensible" : 0,
			"homepatcher" : "",
			"max_version_max" : "none",
			"max_version_min" : "7.1",
			"name" : "Mira",
			"os" : 			{
				"macintosh" : 				{
					"platform" : [ "ia32", "x64" ],
					"min_version" : "none"
				}
,
				"windows" : 				{
					"platform" : [ "ia32", "x64" ],
					"min_version" : "none"
				}

			}
,
			"version" : "1.2.1",
			"website" : "https://cycling74.com",
			"domain" : 32,
			"domains" : 32
		}
,
		"VIDDLL" : 		{
			"author" : "Rob Ramirez",
			"description" : "The VIDDLL package installs a Jitter video engine adapter for jit.movie, allowing file playback via the VIDDLL library.\n\nVIDDLL is an interface and set of utilities for cross platform, high performance, random access video playback. VIDDLL is copyright Paul Bamborough and Julian Storer. \n\nThis software uses code of FFmpeg - http://ffmpeg.org - licensed under the LGPLv2.1 - http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html - and its source can be downloaded here - https://cycling74.s3.amazonaws.com/download/ffmpeg-3.0.2.tar.gz",
			"displayname" : "",
			"extends" : "",
			"extensible" : 0,
			"homepatcher" : "",
			"max_version_max" : "none",
			"max_version_min" : "7.3.4",
			"name" : "VIDDLL",
			"os" : 			{
				"macintosh" : 				{
					"platform" : [ "ia32", "x64" ],
					"min_version" : "10.9.x"
				}
,
				"windows" : 				{
					"platform" : [ "ia32", "x64" ],
					"min_version" : "7"
				}

			}
,
			"version" : "1.1.4",
			"website" : "https://cycling74.com",
			"domain" : 32,
			"domains" : 32
		}
,
		"Video and Graphics" : 		{
			"author" : "Cycling '74",
			"description" : "Video and Graphics programming tutorials",
			"displayname" : "",
			"extends" : "",
			"extensible" : 0,
			"homepatcher" : "",
			"max_version_max" : "none",
			"max_version_min" : "7.2",
			"name" : "Video and Graphics",
			"os" : 			{
				"macintosh" : 				{
					"platform" : [ "ia32", "x64" ],
					"min_version" : "none"
				}
,
				"windows" : 				{
					"platform" : [ "ia32", "x64" ],
					"min_version" : "none"
				}

			}
,
			"version" : "7.2.0",
			"website" : "http://www.cycling74.com",
			"domain" : 32,
			"domains" : 32
		}
,
		"Vizzie" : 		{
			"author" : "Cycling '74",
			"description" : "With VIZZIE, you just grab a few simple modules, connect them together and almost instantly have a VJ rig or interactive video work, complete with real-time effects.",
			"displayname" : "",
			"extends" : "",
			"extensible" : 1,
			"homepatcher" : "",
			"max_version_max" : "none",
			"max_version_min" : "6.1.10",
			"name" : "Vizzie",
			"os" : 			{
				"macintosh" : 				{
					"platform" : [ "ia32", "x64" ],
					"min_version" : "none"
				}
,
				"windows" : 				{
					"platform" : [ "ia32", "x64" ],
					"min_version" : "none"
				}

			}
,
			"version" : "1.0.2",
			"website" : "http://cycling74.com/2010/11/19/introducing-vizzie/",
			"domain" : 32,
			"domains" : 32
		}
,
		"Lyon Package" : 		{
			"name" : "Lyon Package",
			"domain" : 4,
			"domains" : 20
		}
,
		"ml.star" : 		{
			"author" : "Benjamin D. Smith",
			"description" : "A toolbox of unsupervised machine learning algorithms implemented in Max to support on-line learning, and real-time interactive music and video, aimed at the non-expert computer artist.",
			"displayname" : "",
			"extends" : "",
			"extensible" : 0,
			"homepatcher" : "ml.star.maxpat",
			"max_version_max" : "none",
			"max_version_min" : "none",
			"name" : "ml.star",
			"os" : 			{
				"macintosh" : 				{
					"platform" : [ "ia32", "x64" ],
					"min_version" : "none"
				}
,
				"windows" : 				{
					"platform" : [ "ia32", "x64" ],
					"min_version" : "none"
				}

			}
,
			"version" : "1.0.0",
			"website" : "http://ben.musicsmiths.us",
			"domain" : 4,
			"domains" : 4
		}
,
		"Dualities Package" : 		{
			"name" : "Dualities Package",
			"domain" : 16,
			"domains" : 16
		}
,
		"FFTease 3.0 Package" : 		{
			"name" : "FFTease 3.0 Package",
			"domain" : 16,
			"domains" : 16
		}
,
		"HoaLibrary-Mac-v2.2" : 		{
			"name" : "HoaLibrary-Mac-v2.2",
			"domain" : 16,
			"domains" : 16
		}
,
		"ICST_ambisonics_2_3_1" : 		{
			"name" : "ICST_ambisonics_2_3_1",
			"domain" : 16,
			"domains" : 16
		}
,
		"Jamoma" : 		{
			"name" : "Jamoma",
			"domain" : 16,
			"domains" : 16
		}
,
		"Lyon" : 		{
			"name" : "Lyon",
			"domain" : 16,
			"domains" : 16
		}
,
		"LyonPotpourri 3.0 Package" : 		{
			"name" : "LyonPotpourri 3.0 Package",
			"domain" : 16,
			"domains" : 16
		}
,
		"myo" : 		{
			"author" : "Jules Françoise",
			"description" : "An external for communicating with the Myo Armband",
			"displayname" : "Myo for Max",
			"extends" : "",
			"extensible" : 0,
			"homepatcher" : "myo.maxhelp",
			"max_version_max" : "none",
			"max_version_min" : "6.1.0",
			"name" : "myo",
			"os" : 			{
				"macintosh" : 				{
					"platform" : [ "x64" ],
					"min_version" : "none"
				}
,
				"windows" : 				{
					"platform" : [ "ia32", "x64" ],
					"min_version" : "none"
				}

			}
,
			"version" : "0.1.3",
			"website" : "https://github.com/JulesFrancoise/myo-for-max",
			"domain" : 16,
			"domains" : 16
		}
,
		"Max-SDK" : 		{
			"author" : "Cycling '74",
			"description" : "Max Software Development Kit",
			"displayname" : "",
			"extends" : "",
			"extensible" : 0,
			"homepatcher" : "",
			"max_version_max" : "none",
			"max_version_min" : "7.1",
			"name" : "Max-SDK",
			"os" : 			{
				"macintosh" : 				{
					"platform" : [ "ia32", "x64" ],
					"min_version" : "10.7.x"
				}
,
				"windows" : 				{
					"platform" : [ "ia32", "x64" ],
					"min_version" : "7"
				}

			}
,
			"version" : "7.1.0",
			"website" : "https://github.com/Cycling74/max-sdk",
			"domain" : 16,
			"domains" : 16
		}
,
		"MIAP_for_Max" : 		{
			"name" : "MIAP_for_Max",
			"domain" : 16,
			"domains" : 16
		}
,
		"myo-for-max-0.1.3" : 		{
			"name" : "myo-for-max-0.1.3",
			"domain" : 16,
			"domains" : 16
		}

I am seeing  high CPU usage from a very simple gen~ codebox program that reads two buffers and interpolates and writes their contents into a

gen~-buffer-access-through-codebox-seems-pricey

Given that the interpolation loop is run once per sample, the CPU rate now seems reasonable to me. Running the loop at the control rate, which is appropriate for this algorithm, results in much lower CPU demand. (Around 2% for a vector size of 64, compared with near 0% for a comparable algorithm coded in C as an external.)

Yep. There are times when control rate just makes more sense.

gen~ buffer access through codebox - seems pricey