Logic Pro X 10.2.4 - CPU load distribution

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edryck Author

Level 1

8 points

Logic Pro X 10.2.4 - CPU load distribution

I am brand new for Mac, Logic Pro X and Mac Pro.( come from Win98 - Cubase & Win7 - Sonar 8.5 ).

Is there a strategy or procedure to follow for the distribution on the CPU load.

Every first Software Instrument ( Omnisphere, Capriccio, Nexus, Kontakt ..... ) you start on a Channel Strip

uses the right side of the CPU Monitor meter. Sometimes so high that you can even not record a serie

of notes ( depending on the used patch of course ).

If you succeed to record a serie of notes, then the distribution on ajacent CPU's begins on the left

side to build up, but I don't know when or how this process will start.

Sometimes the right side thread stays at its maximum and won't distribute to other CPU's.

Distribution sometimes begins when - you start stop during playback - put an audio track in record mode - load a

new instrument in a track - add additional instruments and tracks - put more tracks in record mode - just

sit and wait for some time when the playhead passes the end of the recorded track...........

I made a template with 24 different Instrument Channel strips. Same problem to start ( with some patches ).

Once establised it stays O.K. ,but the start with some complex instruments is difficult.

( one solution can be : don't use these patches )

Some settings :

Sample rate 96kHz - Buffer Size ( changed from 32 to ) 512 samples - 24 bit

Apollo Twin audio - Playback & Live tracks - Processing treads >automatic

If somebody can help. Thanks in advance.

Mac Pro (Late 2013), OS X El Capitan (10.11.5), 12-core - 64 GB - D700 - 1TB PCI

Posted on Sep 17, 2016 5:32 AM

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Answer 1

kerochan

Level 4

1,071 points

Sep 17, 2016 11:30 AM in response to edryck

Hi edryck

I hope someone can help you with your question! coz I don't understand a word of it! I am baffled!

But I would like to understand!

I have had Logic Pro X with a Macbook Pro 15 for a few weeks, so I am new to it, but I have had no problems.

Good luck!

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Answer 2

Pancenter

Level 6

14,788 points

Sep 17, 2016 8:53 AM in response to edryck

Couple of things... this is one of the only Apple help articles on balancing within a project, it's related but not exactly the same as your question.

Logic Pro/Express: Tips for balancing multi-core performance - Apple Support

However, the first threes sentences read:

"Logic breaks tasks down into threads that can be assigned to a single core for execution. It's not possible to split a single thread across multiple cores, although a single core may run multiple threads at the same time. This is one reason that you may sometimes see uneven load distributions across the available cores on your computer."

Basically, a single channel strip comprises a single thread, at one point the operating system was going to jump in a manage threads across tasks but Logic itself manages threads as the article said. So, a channel strip no matter how many CPU sucking plugins it's using can only use a single CPU core... and... a single core can manage several threads so yes, before the load starts getting distributed you may see a single core loaded up. I also use a few quick stop/starts to begin distributing the load.

There one other item, when Logic is stopped it mostly stops all active CPU use, this means that buffers feeding data into plugins as well as virtual instruments is not happening... so if you're in a complex arrangement and scroll to a new place in the song and hit play, you may see a dramatic CPU hit and/or a System Overload message. Or, if you load a virtual instrument while Logic is stopped and immediately play it you may miss the first note or two as the VI responds to MIDI and fills the audio out buffer. Usually a one-time occurrence.

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Answer 3

CCTM

Level 6

13,159 points

Sep 17, 2016 8:55 AM in response to Pancenter

Hi

Further to this:

Logic Pro X 10.0.7 or later: Processing Threads setting and Core Usage - Apple Support

and

About the Multithreading setting in Logic Pro X - Apple Support

CCT

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Answer 4

edryck Author

Level 1

8 points

Sep 17, 2016 11:33 AM in response to kerochan

Thanks anyway for your concern.

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Answer 5

edryck Author

Level 1

8 points

Sep 18, 2016 5:24 AM in response to Pancenter

Thanks for your reponds and additional info. That is exactly what happens as you describe.

Though, it is sometimes very difficult with a Complex Sound to start recording the first track without

hearing glitches or crackling. Often I get than also a message like " can not synchronise 96.000Hz .... " while

recording or playback stops and restarts ( with a begin of CPU distribution ).

Perhaps better start with a simple sound and then continue with more heavy CPU eaters.

Your response was very helpful.

Thanks

Eddy

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Answer 6

edryck Author

Level 1

8 points

Sep 18, 2016 5:26 AM in response to CCTM

Thank you for this additional info. I found this links very helpful for my problem.

Regards

Eddy

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Answer 7

BenB

Level 6

13,438 points

Sep 18, 2016 6:46 AM in response to edryck

Reduce I/O buffer size.to 64.

Processing Threads to Automatic.

Process Buffer Range to Large.

I use the same Mac Pro, and have no issues at all. I do very heavy compositions for broadcast and film using a ton of Native Instruments plugins. I keep all my projects and audio records set to an external drive (T'bolt RAID).

Don't obsess with how the CPU distributes processing. Not all processes can, nor should be distributed (evenly across all cores). So close that floating window and ignore it. What drive are you putting your projects and such on?

What percentage of your system drive is left as free space?

Launch Disk Utility and run First Aid on all drives.

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Answer 8

Pancenter

Level 6

14,788 points

Sep 18, 2016 2:01 PM in response to BenB

BenB wrote:

Reduce I/O buffer size.to 64.

Processing Threads to Automatic.

Process Buffer Range to Large.

I use the same Mac Pro, and have no issues at all. I do very heavy compositions for broadcast and film using a ton of Native Instruments plugins. I keep all my projects and audio records set to an external drive (T'bolt RAID).

And are you using a 96kHz sample rate like the original poster? 96kHz takes a toll on the CPU and system resources.

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Answer 9

BenB

Level 6

13,438 points

Sep 18, 2016 5:36 PM in response to Pancenter

Personally, yes I do, without issue.

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Answer 10

edryck Author

Level 1

8 points

Sep 19, 2016 8:04 AM in response to BenB

BenB,

Thanks for your help.

There are some patches with a project sample rate of 96kHz that I can certainly not play on my laptop dual, desktop i7 and now also not on the Mac Pro. I can give you some examples, but I'm not sure if you may post manufactering names and patches.

If I put the sample rate on the Mac Pro to 44,1 or 48kHz with your suggested options it's O.K.

Does it make sence to record with 96kHz or 48kHz ( for internet, Youtube or CD 44,1kHz ).

Original SSD disk has more than 500GB free space.

Except some libraries and AU instruments nothing else has been installed.

This is a brand new machine ( only 1,5 months ).

Projects and libraries are on the HD Macintosh internal drive.

Only a Lacie external disk for Timemachine.

All the rest works fine, but I just wanted to know the reason why some patches stay maximum on the rightmost CPU, and are very difficult to get spread on adjacent CPU's. There is an annoying crackling noise during recording and Logic stops. So, very difficult to record these pathes ( solution = don't use these ). What can be so special at these.

Other projects with more than 40 tracks ( tested until now ) even on 96kHz work O.K. but with these patches ....?

Any comments welcome.

Regards

Eddy

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