I love using Logic, but I'm having trouble with it lately. When doing projects in 24bit/96KHz with about 3 audio tracks and 5 instrument tracks my Audio meter (on the Logic system performance gauge) goes into the red, but the CPU meter is at less than half. About half the time it'll actually overload and stop. Here's my setup:

Dual 867 G4, OS 10.3.5, 768MB ram, Logic Big Box 5.5, seperate 7200 rpm 40GB ATA/100 hard drive for audio files.

I know Logic Big Box (same as Logic Express) does not take advantage of dual processors, but it seems like a single 867 G4 should be able to handle more than 3 audio tracks and a couple instruments.

My question is: Is my problem the hard drive or CPU or something else? Just wondering if anyone has any suggestions.

Thanks for any help.

In OS X, every program use both processors. The management is system wide, not application wide as it was in OS 9 (a nasty DIY software solution, now it's well tailored and smooth).

I wonder if it's not the 96 Khz handling doing a capricioso.

Was it sluggish too in prior OS X version or only 10.3.5?

Also, have you disabled journaling on the drive hosting the files? If not, you SHOULD.

Thanks for the info, first off.

"In OS X, every program use both processors."

I've spoken to Emagic and they say Big Box and Express don't have "Multi Processor Support" (it also says this on their website). How would OS X use both processors in this case?

"Also, have you disabled journaling on the drive hosting the files? If not, you SHOULD."

How do I go about doing this and what is the benefit?

Thanks again.

This post has been edited by whickus: Mon 27 Sep 2004, 01:37

I don't know what emagic has done, but processor usage is MACH kernel in the Core OS X matters, it's no application business as it was in OS 9. I don't see the benefit of doing so (if it's possible, the guy at emagic may be wrong But if it's the case it's clearly to bother users by actually limiting the power they can use on their computer, which is baaaaaaad. Not that Digidesign does that with protools and the coreaudio driver, which from an Mbox to a $300000 system can't play itunes while having a Protools session open… mad!

Ooops… I wans ranting… and I've browsed emagic website in the logic flavours comparison charts… You're right.

Shame on them! you're usung only one processor. :sad which means your logic scramble the raw power for a goal, thanks emagic!

That explains par of the problem.

Journalling is a OS feature, it's a way to manage hard drives (especially ones with sensitive data on, or your system drive.

Journaling permits in case of crash to return to a previous "healthy" state of the drive to minimize consequences. The trade-off is that performances are slightly lower but it's more prone to be seen on disk intensive operation. Digidesign warned officially to not journalise drives where you are working on midi/audio and keep the system elsewhere on a journaled drive.

Now, journalising is decided when you format the drive. To start it or stop it after that, open the Apple Disk Utility, select the drive and press the relevant button on top right.

The processor stuff explains a lot… Now maybe journalling is on on the relevant drive (keep it on the system drive), but there can be also another reason… If you never let your computer on all night too, it wont run its BSD clean up routine, trash the logs, etc. Also each time you install something, whatever it is on OS X, repair your authorizations!!!!!!!!!!!!!!!!

To repair authorizations, use the disk utility.

And to run the scripts for maintenance, you can do so with MacJanitor, you can leave your computer on one night a week. But you can use OnyX (download) which is free and allows you to tweak a few other things. Xupport which is a shareware as even more tricks in its bag.

Hey, thanks alot lepetitmartien!

As soon as I opened Disk Utility last night, I saw the Journaling options. My Projects HD already had Journaling Disabled, but after Repairing Permissions, I noticed the load was a little lighter. Still, the fact that I have a DP machine and not be able to use them both for the apps that count is a little discouraging.

I just have one more question then I'll be off you're back:

I'm going back to school and knowing I'm really only using a single 867 G4 (with Logic at least), I'm seriously considering selling my PMac and buying an iBook 1GHz G4. The new iBook specs seem to be really similar to my PowerMac. I've weighed the pros and cons and here's what I came up with:

Pros of iBook
-1 GHz G4
-portability
-wireless 802.11G
-internal Bluetooth
-USB 2.0
-maxes out to more RAM than I currently have

Cons of iBook
-no level 3 cache
-slow hard drive speed

Bus speeds are the same on both machines and I'd also upgrade the hard drive to 60GB. So my question is: What kind of performance can I expect out of Logic Express on an iBook with these stats?

Thanks again for your help

I thought that might be useful.

iBooks are not exactly tailored for intensive tasks. The lack of level 3 cache is a bad thing too (less efficiency). maxintosh is right on the hard drive… For performance, you should ask a logic user

Now when you're serious while making music on a laptop, you have another fast drive around in firewire…

Powerbooks are more expensive but fast mojos.

I'm currently wondering which will be my next computer and i'm scratching my head (if Apple could offer it to me whatever it is, it'll be most welcome