CPU Spikes - 64bit better than 32bit on Mac?

Getting CPU overload spikes, generally when recording (MIDI only though).
Weird. And annoying.

My Mac based setup is a 6 core single MacPro, and feeding to a couple of VSL slaves. This could be a cause maybe. Plugs - avoiding Powercore although it is installed (all this under latest Lion).

I also generally have Apple’s Remote Desktop application in the background to control said slaves, and note that this can be a bit of a hog (50% of a single CPU sometimes). On a separate network to VSL.

Now, I have started running Nuendo as a 64 bit Ap and the spikes are seemingly gone. Yet I was no-where near memory limits when under 32 bit.

Anyone else found this the case?

Please don’t ask for a report on latency settings etc, as the usual PC/Mac debate will raise it’s head. The issue seems un-related to CPU “load” as such, the spikes just occur out of the blue.

Thanks for reading.


Are there any limitations for you when running the 64 bit version? (do you need a lot of 32 bit plugs?)

I have started to use N5.5 64 bit on different Macs with extremely large sessions including entire seasons of sitcom mixes recently and strangely felt like N5 had suddenly more power than before. Maxing out with CPU spikes or slow GUI response hasn’t happened yet.
The only thing that really annoys me like*&"%! is that AAF import is not available in 64 bit mac (well, it’s available but it does not actually work!), so I need to import files in N5 32 bit and then import into 5.5x.


Not hugely missing the 32 bit plugs, although deliberately trying to wean myself of the whole Powercore set. In the event that you need to nose one, the bridge thing works quite well (although clunky).

I agree, it seems smoother overall .

But had a spike an hour ago… compared to every few minutes under 32 bit perhaps there is something “freed up” by being in 64 bit.

A mystery.


…that I don’t mind