Logic Pro only using 1 core.

Question

Level 1

5 points

Logic Pro only using 1 core.

I am using logic pro 9.1.8 in 64 bit mode with a 32g RAM, 3.4gHz quad core i7 processor on a 2011 iMac.

In some of my projects, the last core is the only one used, and in other projects, there is better distribution of CPU usage.

I know about spreading plugins over buses, but that doesn't change the fact that only one core is used.

This problem has nothing to do with buffer size, and I have also trashed my preferences.

Is there another solution?

Logic Pro, Mac OS X (10.7.5)

Posted on Apr 2, 2013 8:50 PM

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Answer 1

CCTM

Level 6

13,045 points

Apr 3, 2013 12:48 AM in response to xiaoanguitar

Hi

Perhaps these willl help?

http://support.apple.com/kb/HT3161

http://support.apple.com/kb/TS3834

http://support.apple.com/kb/HT4426

CCT

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Answer 2

xiaoanguitar Author

Level 1

5 points

Apr 3, 2013 1:54 AM in response to CCTM

I have read all those documents, and they don't help. The only one that looked like it might work was manually increasing the number of threads, and that doesn't do anything.

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Answer 3

CCTM

Level 6

13,045 points

Apr 3, 2013 1:58 AM in response to xiaoanguitar

Hi

So you know that Logic assigns processor cores per channel strip signal flow, and that the last core is typically reserved for the currently selected "live" channel?

Are you using any processor-intensive plugins?

Have you tried selecting an empty audio track (with the Inputs set to 'No Input")?

What buffer size are you running at?

Perhaps a screenshot of your Arrange & Mixer would help?

CCT

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Answer 4

xiaoanguitar Author

Level 1

5 points

Apr 3, 2013 7:36 AM in response to CCTM

The buffer size method doesn't really change the spiking for me.

Selecting a single audio track during playback helps somewhat but it still spikes occasionally.

I'm using a few instances of convolution reverb but I realized what really causes the last core to go crazy is the use of 32 bit plugins while in 64 bit mode. Getting rid of them and substituting them for 64 bit equivalents seems to make the program run fine.

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