32 bit logic and OSX maximum memory usage question

Hi. Please can someone confirm things.
Suppose I have 6GB of RAM and running Logic in 32 bit mode.
Can my operating system run 2GB of RAM and logic 4GB, or is the total RAM usage possible for both the OS and Logic max out at 4GB?

Yes, the EXS24 also uses some additional memory. So you are probably fine.

The disadvantage of the 32-bit version is, that it will crash if you run out of 4GB address space, while the 64-bit version at some point will just loose performance.
Hi Thanks for your answer, but not clear as I am asking an 'or' question.
If I got 6G of RAM:
Can Logic use 4 Gig of RAM and the OS 2 Gig of RAM (if logic is in 32bit mode)?
To answer your question: yes, Logic and Mac OS 10.6 can use more than 4 gig combined.

Some details: Logic, in 32 bit mode, starts to become unusable and will corrupt your projects at about 2.6 gig or so of Logic own ram usage.

Another thing: even in 32 bit mode, some things, EXS for example, that have their own separate and additional ram they can use as long as they are set up for it (for example, if you have 6 gig or ram, and you want to run 3 gig of EXS samples, plus a bigger session that needs 2 gig to run, you are ok).

Most current 3d party sample players have their own 64 bit ram servers available that don't have limits other than the entire amount if ram you have. If you had 15 gig or ram like I do, You could run Logic with 2 gig ram, the EXS server can be running 4, the Play server can be running 4, and Kontakt or VSL each running 3. Once the system gets close to using the entire system ram like this, you will find your session will become very sluggish.
Wow! Very informative answer thanks.
Actually before I posted this I phoned an Apple "genius" and he told me the other, that when running logic in 32bit the entire system is tied down to just 4GB. This did not seem right hence the post.
Also great news for me, that 3rd party AU plugs can access more RAM outside logics 4GB limit, or better said 2.6GB (to be stable). So I presume then running plugs like Omnisphere has little effect on the safe 2.6GM limit, if you got enough RAM to do so?
Thanks. Looks like I better go and but some more RAM...
More ram is always a good thing, especially with Spectrasonics' stuff. Ram is cheap, and to "filler up: when it comes to memory is a great idea.

You don't mention which Mac you have, nor the OS, as these things will actually affect what the correct answer is. With 10.5 (a 32 bit os) I imagine the 4 gig limit to both IS the correct answer. Snow Leopard is a 64 bit os that can run 323 bit apps without any issues, so the 4 gig ram limit is not longer applicable.

As for the Apple "genius" bar people, most are younger than the age of my first Mac (28 years ago), for sure younger than my first high school mainframe computer (1973 for those that wanna know). I gain some info every now and then but I find them to be under informed, or mainly unexperienced in the nuances of these systems when it comes to music applications. I have seen more than a few blank looks when I try and get an answer, even from the top guys art a store.

So, in this case, a second opinion is a very good thing. There are a number of us that have been on this board (or the 2 incarnations that came before it) for about 18 years no, long enough to get a few issues worked out:)

Welcome and good luck!
The info that was shared was incorrect.
In case of OSX 10.6.8 on imac i7

Even with now 16GB of RAM when logic is run (at least in the case with Kontakt and Omnisphere) Logic RAM usage and OS RAM usage can still only utilize 4GB of RAM max combined.
So for example if the OS is using 2GB of RAM, Logic will run out of memory if it is using 2GB or more.... Tried and tested now
Even with now 16GB of RAM when logic is run (at least in the case with Kontakt and Omnisphere) Logic RAM usage and OS RAM usage can still only utilize 4GB of RAM max combined.

The OS only uses a few MB out of the 4 GB address space. For more than 4GB, you should enable 64-bit. With 32-bit AudioUnits you have to use the bridge, which will again limit you to 32-bit. In that case: ask the developer of the AudioUnits to _finally_ deliver 64-bit ones - it's not that this is news...
Yes, you couldn't have had 64 bit enabled, as well as the server in Omnisphere or the Kontakt memory manager enabled.

Enable them and let us know how it goes. I can assure you that it will work, and that it's only the lack of experience that is getting the results you are getting ;-))
I did a test last night, loaded a 32 bit version of Logic and loaded Kontakt, Omnisphere, Addictive Drums, and used the composer template for electronic music figuring it would use some stuff I also added a 1/2 gig piano. I took a screen shot showing as much detail as I could, and save it as an attached file...

If you take a look, you will see clearly that there is much more than 4 gb combined with Logic and what I would consider the system.

I am wondering where you determined what you "system" ram use was. Could you please explain? I am interested in how you came to your conclusion.

I hope this clears up the confusion around running a 32 bit version of Logic with audio plug-ins that have their own independent 64 bit memory servers (Logic EXS, Kontakt, Omnisphere, in a 64 bit OS).


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Hi Thanks everyone for all your time to answer. I do fully understand the 32/64 bit differences.
My original question was:
"Suppose I have 6GB of RAM and running Logic in 32 bit mode"
There are reason I want to run in 32bit only. Mainly bridge mode really is an awkward interface and more importantly I am always bouncing between my 64bit imac and 32bit macbookpro for live gigs and portable studio use. Once you start working in 64 bit you can not open it up on a 32bit machine. (Correct me if I am wrong on that point)
My hope was to find a way so Logic in 32bit can utilize ALL the 4gig and the rest of the RAM use used to run the OS. But unfortunately this is not the case, and as georgelegeriii correctly identified logic in 32bit can not really use more than 2.6gig of RAM.
Thanks all!
I am always bouncing between my 64bit imac and 32bit macbookpro for live gigs and portable studio use.

Care to elaborate on what you mean by "64 bit iMac and 32bit macbookpro"?

Once you start working in 64 bit you can not open it up on a 32bit machine. (Correct me if I am wrong on that point)

IF by that you mean, if you work on a Logic project in Logic 64 bit, and then want to open it in Logic running in 32 bit, you should be able to do this, unless of course in building up the project in 64 bit you get to a stage where it requires more memory then can be addressed in Logic in 32 bit mode.

Some experimentation on your part is probably advisable, along with contacting those 3rd party AU developers who still haven't released 64 bit versions of their plugins and pestering them to do so ;)

kind regards

I go back and forth between 32 and 64 bit Logic, depending on how much sample data I intend to use, and how much system ram Logic is asking for. A Memory alert will pop up as Logic gets close to being overloaded. Shut down, and switch to 64 bit more. OR bounce your tracks and clear Logic's VI's out.

So, yes, to correct you, Logic can go back and forth between 64 bit and a 32 bit session.
My bad! Sorry it was a few months since I tried to do this and encountered these problems.

You can go between 64bit and 32bit sessions perfectly unless like in my case you are using Novation 'automapped' plugins, that don't seem to be working in 64bit mode, and then are 'missing' and messing up your session.

This is why I remember I was having problems going between 64bit and 32bit; It is because most my plugs are Automapped.

I just Updated to Automap 4 today, spent 3 hours to get it to work in 64bit, but still not working.

Thanks and sorry for the incorrect information. So I am still stuck in 32bit :(
Have you contacted Novation about this? Is there any relevant information on their website?

kind regards

FWIW, I am running automap 4.3 with a Novation Impulse keyboard in Logic set at 64 bit mode with no problem. Admittedly I haven't tried moving between 64 and 32 bit operations with Automap plug-ins instantiated in the project; but the 64 bit implementation of automapped plug-ins does seem to be solid and robust in general.
Wow. I really cant get Automap 4.3 to work with Logic.

Re-installed all drivers, restored all Novation SL to factory setting. Updated the Novation SL, re-installed Automap 4.3

Got to logic set up controllers. Scan all models...get the automap mixer to appear, input output ports set corectted. Do the environment monitor port thing...

Still when I go to Template 39 it says "Logic is Offline"

When I go to Template 38 and go to the mixer View, all the mapping is all over the place.

Ouchh. In 32bit everything works fine.

It seems like Automap is implemented slightly differently with the various Novation controllers. Mine doesn't use templates the same way the SL does. Maybe that accounts for some of the anomalies? Have you tried contacting Novation support? They can be a bit slow to reply sometimes, but I have found them to be very helpful overall.....
Hi will probably not contact Novation, really too busy with music production. If it does not work, I tend to move on. If it's not broken I tend not to update. So probably have to stay in 32bit and just keep printing stems, which is actually a safe work flow anyway.