CPU does not appear stable with Lion and Logic Pro 9.1.7. Very light load. What gives?

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lemmynaught Author

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CPU does not appear stable with Lion and Logic Pro 9.1.7. Very light load. What gives?

Testing new Lion and Logic Pro install. Only two tracks recording 44.1. CPU is spiking all over the place. What gives?

Logic Pro, Mac OS X (10.7.3)

Posted on Apr 26, 2012 6:56 PM

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Answer 1

Pancenter

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Apr 26, 2012 11:47 PM in response to lemmynaught

Could it possibly be that Spotlight hasn't finished indexing the drives.

Or... the new OS (Lion) is top heavy, the graphics are su-ck up a lot of CPU so the other possibility is you have an older graphics card that Lion is not completely compatible with.. but that's just a guess.

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Answer 2

Pancenter

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Apr 27, 2012 12:04 AM in response to lemmynaught

Addendum..

Does the CPU spike when you scroll the arrange window?

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Answer 3

lemmynaught Author

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Apr 28, 2012 12:56 PM in response to lemmynaught

No. Seems to bounce around no matter what. Perhaps Symphony Mobile Express Card is at fault? Running in 32 bit environment? Seen lots of discussion regarding the CPU stability - could the threading be a bit agressive?

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Answer 4

Pancenter

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Apr 28, 2012 1:28 PM in response to lemmynaught

Any CPU hungry threads showing up in Activity Monitor.

What are you running the Preferences/Audio I/O buffer at?

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Answer 5

lemmynaught Author

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Apr 28, 2012 1:51 PM in response to Pancenter

32 bit.

Know that is low but did not notice an issue when using Leopard.

Still bouncing around but for some reason not as high as the other day. Recording two audio tracks the other day the activty monitor was acting like it had finished a couple pots of coffee right before I hit record. Bounced as high as 80 - 95%. Today for some reason Logic is hovering around 40% and core audio around 27% and a lot more stable. Still a bit bouncy though.

Strangeness. Maybe another service was running.

Any heads up you give in case it starts acting up again would be appreciated otherwise thanks for your responses.

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Answer 6

lemmynaught Author

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Apr 28, 2012 2:00 PM in response to lemmynaught

In regards to when Logic was bouncing around did not notice any CPU intensive services running and the CPU was bouncing from about 10% to 95%. To me looked like it was allocating a lot of resources managing threads. If I remember correctly the thread count looked a little fishy at the time.

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Answer 7

Pancenter

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Apr 28, 2012 2:14 PM in response to lemmynaught

lemmynaught wrote:

32 bit.

Know that is low but did not notice an issue when using Leopard.

I know you're runnng in 32-bit mode.

May I ask what the Preferences/Audio/ I/O Buffer is set at?

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Answer 8

lemmynaught Author

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Apr 28, 2012 2:51 PM in response to Pancenter

Sorry, 32 samples. I did test by moving to 64 but the issue persisted if I remember correctly..

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Answer 9

Pancenter

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Apr 28, 2012 3:05 PM in response to lemmynaught

While you may not have had problems in Leopard, Lion is a much bigger resource hog, are you using the latest Symphony Mobile 4.2 release? Just for an experiment try both a 128 and then a 64 I/O Buffer and see if there's a performance shift.

Anyway, you're right about some of Lions internal workings being more aggressive, plus, the latest Logic does not seem to be as efficient as earlier versions.. seems like Apple is experimenting with task priorities trying to find a balance.

I don't think the very low latency you achieved under leopard will be attainable, however, there is a new Lion on the horizon.

Also, experiment with the process buffer size and set the number of Processing Threads (CPU Cores) by number rather than Auto.

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