An Experiment for Mac Users

[pj]

Using unix "kill" or any other brute force means of terminating coreaudiod is likely to give the results you have experienced. The fact that coreaudiod is relaunching indicates that the system expects coreaudiod to be running. The best way to disable coreaudiod is using launchctl as described at the end of this post.

 

cheers

Paul

 

[cfmsp]

 

thanks again, CG, who sent me this:

 

"http://www.lachoseinteractive.net/en/products/processwizard/

 

...is an easy way to fiddle with renicing. It'll show up in your menu bar after you launch it. You can use the sliders to change the process priority. Once you restart the computer, it will disappear from the menu bar, and whatever settings you change will go away, until you relaunch it and start over again. You want to slide iTunes (or Play, in my case...) as well as coreaudiod all the way to the right."

 

Coreaudiod is hidden in "Non user processes".

 

If you wonder the impact, set the slider for say Amarra all the way to the left, and you get crackling when you do anything at all.

 

Process Wizard is great for experimenting with various re-nicing options prior to finalizing a login script, should you prefer the latter.

 

clay

 

 

[cfmsp]

CG said, a couple of weeks ago:

 

"Ask your software author to offer this option."

 

Jon Reichbach has sent me an apple script that can be initiated at Login to automatically start Amarra with high priority.

 

As far as I know, this has not been offered on the Amarra site, and therefore is not an official Amarra release - read, not supported by Jon.

 

Jon gave me permission to release it 'into the wild' (my words, not his) if I heard an improvement. Since I did hear such, much to my surprise, I am sharing it here with all interested.

 

Those without Apple Script experience may be able to simply paste this into Apple Script and modify this to his/her heart's content.

 

enjoy,

clay

 

PS, I was unable to attach the Script itself as CA only allows certain types of attachments.

 

EDIT:

First 10 to do so can download the Script here:

http://rapidshare.com/files/332757319/LaunchAmarra.scpt.html

 

I can post an Amarra Mini Script, if anyone wants it.

 

 

 

[silverlight]

Clay - thanks for the script, I was able to download it (direct from CA on your first post). modd'ing it now a little to add a couple other processes, adding user/password, etc.

Curious to hear the impact!

 

[cfmsp]

Silverlight,

 

since you asked about modifications for user access, i'll attach what Jon told me - should have done this earlier.

 

"This script will always ask for administrator access.

This can also be Fixed by adding your user name to the

 

/etc/sudoers file

 

The "sudoers" file in /etc should have lines similar to those found in "sudoerstext". This enables the specified users (in this example, both 'jon' and 'admin') to execute the nice and renice commands via a call to sudo without entering a password. This is required as only superusers are able to promote a process' priority above normal

 

%jon ALL=(ALL) NOPASSWD: /usr/bin/renice,/usr/bin/nice

%admin ALL=(ALL) NOPASSWD: /usr/bin/renice,/usr/bin/nice

 

I tried this then replaced the file as I did not want to change this file on my main development system."

 

cheers,

clay

 

 

 

 

[cfmsp]

 

For those interested, this is the version of the Amarra script for the Mini.

 

 

http://rapidshare.com/files/332780115/LaunchAmarraMini.scpt.html

 

enjoy,

clay

 

 

[cfmsp]

I think I'm gonna disagree with my friend CG on re-nice-ing the coreaudiod process.

 

I can't see that it would have much impact. As evidence, I watched in Activity Monitor, and after 40 minutes or so of listening, it used the CPU for 1/3 of a processor second.

 

He did suggest lowering the priority of AppleVNCServer, for those of us operating headlessly, and perhaps Windowserver. Makes sense to me, as these use more of the CPU (on my G5) than iTunes, and Apple VNCServer has similar numbers to Amarra on CPU utilization from time to time.

 

In Activity, Monitor, click on a process and click the 'Inspect' button for the lowdown on any process.

 

As they say, YMMV,

 

clay

 

 

[davidR]

Clay, I know this has been discussed before several times but have you tinkered with running both Itunes and Amarra off of a RAM disk? I had a little trouble getting it to work with the Mini version 1.2 demo but I noticed a small improvement over simply running Itunes alone off of RAM; and when I say off the RAM disk I mean simply copying the Itunes & Amarra icons in Applications and dragging them to it, and then double clicking them within the RAM disk; not actually loading any music files into it. To be honest though after I got my Infinity Shield, Infinity Strings power cable, and CBF Signature from Alan Maher I have thought a whole lot less about tweaks, but they are fun to experiment with still. What other designs of his did you add to your collection?

 

[cfmsp]

 

David,

 

No I did not try this yet. I've installed an SSD for my OS and assumed this would be largely (if not entirely) redundant. thoughts? I do have Chris' script somewhere, and had the intention to try it.

 

As for Alan's stuff, I have some new gear that I've not yet hooked up due to the initial negative effects. I picked up another Quantum Reference Power Conditioner, and a demo Quantum V2, just before the holidays.

 

I'm in the middle of other changes now - just upgraded to ASI Liveline interconnects to great effect - and not yet ready for some 'down time'.

 

Glad to hear you're enjoying Alan's products.

 

clay

 

 

[cfmsp]

 

of course, minimizing the Amarra (graphic) display will dramatically lower the CPU utilization of VNC Server.

 

clay

 

 

[davidR]

Clay as far as the SSD taking care of business vs. the RAM Disk deal I figure it "can't hurt" by any means so it's just something fun to try; even for those with a good SSD. The reason for my noticeable improvement may very well and probably is the fact I am still using a spinning disk, although it's a fast one (10,000 rpm).

 

[jay]

Sorry to take the topic slightly to the left...I downloaded the process wizard softare and can't get it to open up in Snow Leopard. Does it only work on Leopard and earlier? I don't have any of my Macs left on Leopard to try it there.

 

If it doesn't work on Snow Leopard, anyone know of anything similar that does?

 

thanks!

 

[thequietman]

Please

thequietman

 

[cfmsp]

 

I can't attach it here becuase it's file type is not supported by CA (for attachments). I've attached a Word doc, which you can import into Apple Script Editor.

 

Did you try the link I posted to rapidshare?

 

perhaps it reached the maximum of 10 downloads?

 

clay

 

 

 

 

[thequietman]

it worked beautifully

 

[cfmsp]

 

Jay,

 

Process Wizard is quite an old app, and might require Rosetta being installed in order to run under Snow Leopard.

 

clay

 

PS, pay no attention to the man behind the curtain!

 

PPS, that's an inside joke, so seriously, pay no attention.

 

[cfmsp]

For those using the Amarra Mini script, it's been brought to my attention that the instance of Amarra (without Mini) in the script might need to be modified to say "Amarra Mini".

 

This would seem to be the case IF the actual name of the Amarra Mini application (as launched) includes Mini in the name. If not, never mind (in my best Roseannadanna voice).

 

I don't have the Mini app, so I can't really tell. IOW, I didn't test the Mini script before posting it. Shame on me!

 

glad it worked out for you quietman.

 

clay

 

[atomheart]

Since Amarra bypasses coreaudio, shouldn't we only renice Amarra and iTunes?

Thanks

 

[Guest]

Nothing completely bypasses Core Audio.

 

 

 

[same same but different]

May I ask does it all make sense for the newest Mac intel machines? They seem quite powerful to handle even 24/96 flow having huge resources free, aren't they?

 

I may guess that G4-G5 or first Intel Core processors were not really fast enough, but now?..

 

[cbarber]

Howdy, the following applescript renices Amarra, iTunes, and Core Audio. This builds on the script posted earlier in this forum, which I think builds on what Jon of Sonic provided. Thanks to these folks.

 

To use:

 

1) Open AppleScript Editor

2) Copy and paste from below into the editor

3) Change YOUR USERNAME and YOUR PASSWORD to the correct values. Keep the quote marks as they are.

3) File>Save As with the file format set to "Application"

 

Then you just double-click on the application and it will launch iTunes, then Amarra, then checks the PIDs, then sets the nice values. It will confirm for each nice value it sets or will tell you if it encountered a problem. Because you enter your user name and password into the script, it won't prompt for that each time.

 

Just starting to listen with it, don't have any impressions yet. Are others pretty certain this makes a difference?

 

COPY AND PASTE BELOW ------------>

 

 

--Run Amarra

tell application "System Events"

if (get name of every process) does not contain "iTunes" then

tell application "iTunes"

launch

delay 3

end tell

end if

 

if (get name of every process) does not contain "Amarra" then

tell application "Amarra"

launch

delay 5

end tell

end if

end tell

 

--Get process IDs

set theConfirmation to ""

set AmarraPID to do shell script "ps -A | /usr/bin/grep Applications | /usr/bin/grep Amarra.app | awk '{print $1}' | head -1"

set CoreAudPID to do shell script "ps -A | /usr/bin/grep coreaudiod | awk '{print $1}' | head -1"

set ItunesPID to do shell script "ps -A | /usr/bin/grep /Applications/iTunes.app/Contents/MacOS/iTunes | awk '{print $1}' | head -1"

 

try

do shell script "renice -17 -p " & AmarraPID user name "YOUR USERNAME" password "YOUR PASSWORD" with administrator privileges

if (result = "") then

display dialog ("Reniced Amarra with PID " & AmarraPID) buttons {"OK"} giving up after 5

end if

on error errText

display dialog ("Amarra error: " & errText) buttons {"OK"} giving up after 5

end try

 

try

do shell script "renice -16 -p " & ItunesPID user name "YOUR USERNAME" password "YOUR PASSWORD" with administrator privileges

if (result = "") then

display dialog ("Reniced iTunes with PID " & ItunesPID) buttons {"OK"} giving up after 5

end if

on error errText

display dialog ("iTunes error: " & errText) buttons {"OK"} giving up after 5

end try

 

try

do shell script "renice -15 -p " & CoreAudPID user name "YOUR USERNAME" password "YOUR PASSWORD" with administrator privileges

if (result = "") then

display dialog ("Reniced Core Audio with PID " & CoreAudPID) buttons {"OK"} giving up after 5

end if

on error errText

display dialog ("Core Audio error: " & errText) buttons {"OK"} giving up after 5

end try

 

 

 

[Part-Time Audiophile]

Tried this on Amarra Mini -- and changed the pointer to "Amarra Mini.app". But when the display throws up the new PIDs, the Amarra Mini one (the first one) is blank. Seems to me that it isn't "catching" Amarra Mini.

 

Suggestions on what else to change in the script above?

 

Thanks ....

 

[wgscott]

I cannot tell the difference, but I don't have anything making outrageous CPU demands on the system (I've turned off spotlight indexing, for example).

 

This command, by the way, will get you the PIDs you need (if you want to incorporate them in a script):

 

ps -ax | grep iTunes | grep -v grep | awk '{print $1}'

 

The "grep -v grep" keeps the self-reference to the grepping of the string iTunes out of the result.

 

A script like the following does what you need:

 

 

#!/bin/zsh -f

foreach PID in $( ps -ax | grep iTunes | grep -v grep | awk '{print $1}' )

sudo renice -20 -p $PID

end

 

 

You could have launchd run this as a root process every time iTunes is opened.

 

If anyone can actually see a difference, I will be happy to put it together...

 

[Codifus]

I downloaded your script and gave it a go. I don't have Amarra, so with my extremely limited scripting experience, I edited out as much of the amarra code as I could. When I run the app I do still get a few errors upon launching, but iTunes does open up and I can see thru the activity monitor that iTunes has been given more threads than usual, like 13 instead of 7.

 

As to my listening experience, i sense a nice improvement, excuse the pun:) Less digital fatigue? Yeah, kinda. More relaxed? Yeah. Slightly more focussed imaging, less sibilance. All that.

 

I don't know what jitter sounds like but I have the very strange feeling that renicing iTunes in this manner has reduced jitter. I wonder if there is a way to measure that.

 

In my case my iTunes is "driving" an airport express, and I gather that renicing iTunes to have more control over CPU resources has given iTunes, "the tail," so to speak, the ability to wag the dog, aka my airport, with more control:)

 

CD

 

[davidR]

Kill Dashboard, Journaling on the hard drive, Spotlight, Finder, and Rosetta and you will hear a difference. In my system it really gives a more relaxed & less fatiguing sound. It almost adds more volume not in an artificial EQ boosted sense but just more musical information. Just my simple description of a complicated sound.