A note on OSX RAM usage for the MBA crowd

ehfz

macrumors member
Original poster
Jul 24, 2013
41
101
There are a ton of discussions in the MBA forum about how much RAM should one buy to run OSX now and in the future, and many people will cite how much RAM OSX consumes on their 4GB or 8GB laptops. I just wanted to mention as somebody who is running OSX with 16GB of RAM that OSX will happily consume over 8GB of that sitting idle, and will get up to 13GB with maybe 10 tabs open in a web browser. It wouldn't surprise me if OSX idled at even higher RAM usage if I had 32GB or 64GB. It's my understanding based on this that OSX will try to use as much RAM as you can give it to page as much data as it can from the hard drive to the RAM. I say this not to claim that you need more than 4 or 8GB to have a pleasant experience with OSX, but only to state that there's a whole world of potential RAM usage that I don't think the MBA community is aware is possible.
 

motrek

macrumors 68020
Sep 14, 2012
2,317
118
There are a ton of discussions in the MBA forum about how much RAM should one buy to run OSX now and in the future, and many people will cite how much RAM OSX consumes on their 4GB or 8GB laptops. I just wanted to mention as somebody who is running OSX with 16GB of RAM that OSX will happily consume over 8GB of that sitting idle, and will get up to 13GB with maybe 10 tabs open in a web browser. It wouldn't surprise me if OSX idled at even higher RAM usage if I had 32GB or 64GB. It's my understanding based on this that OSX will try to use as much RAM as you can give it to page as much data as it can from the hard drive to the RAM. I say this not to claim that you need more than 4 or 8GB to have a pleasant experience with OSX, but only to state that there's a whole world of potential RAM usage that I don't think the MBA community is aware is possible.
All of your RAM is allocated. Doesn't mean your software is actually using it.

Running all the same stuff on a 4GB machine is almost certainly exactly as fast.
 

vertisync

macrumors newbie
Feb 12, 2015
20
0
All of your RAM is allocated. Doesn't mean your software is actually using it.

Running all the same stuff on a 4GB machine is almost certainly exactly as fast.
This^

I could have 512GB of RAM and let OSX allocate it all, but the stuff that I do will be no faster than it is right now with 4GB of RAM.
 

0983275

Suspended
Mar 15, 2013
472
56
4GB is fine for most people.

But since I run couple of virtual machines and at times, photo processing, 4GB isn't enough (I've done this task with 4GB, wasn't fun), I need 8GB+
 

joshlalonde

macrumors 6502
Jul 12, 2014
422
0
Canada
+RAM != +Speed
+RAM = +More potential for More tasks at a given time

In other words, adding RAM will not necessarily just increase the speed. Your CPU speed is a huge factor in that. If you add it to an old machine, sure it'll appear to speed it up. What really happens is that there is free slots for storing instructions and data. It's faster to access RAM than disk, so if you can quickly grab stuff off RAM, you'll appear to get a boost in speed. If your disk is slow and your CPU is slow, than there's not much you can do but to get a better disk. If you have to replace the CPU, might as well get a new computer.

Now, if you're running a VM, you'll be needing the amount of RAM required by both operating systems simultaneously. In that sense, you need more potential task space, and hence more RAM.

If you are just on your browser, chances are, you'll not be using up all the available RAM space.

Now, let's retire this thread before some smart guy decides that he's going to mention why he got 8GB RAM and that 4GB is trash. That or some 4GB guy says that 8GB is a waste of money.

It depends on your usage, not anything else. And if you want to buy more RAM, go ahead. If you want to buy less, go ahead. But stop trying to persuade others that know about computers why their decisions are inferior to yours.
 

ixxx69

macrumors 65816
Jul 31, 2009
1,119
635
United States
But stop trying to persuade others that know about computers why their decisions are inferior to yours.
Well said Josh.

I think part of why it's a challenging subject is that memory usage is factually based, or at least universally accepted best practices. At any given time when using the computer, RAM is available or it isn't. It's either having an impact on system performance, or it isn't.

So when people interject incorrect or misinterpreted understandings into the discussion, it become a point of do you allow that to continue uncontested or not. Even if it's not to "persuade" anyone, but simply a matter of correctness. Someone will come along and read the thread and be presented with misinformation that they will in turn spread in other threads.

At the same time, there is a portion of the discussion that is valid opinion/decisions that are fairly subjective, e.g. how much "future-proofing" makes sense? or when performance is impacted by lack of RAM, what performance hit justifies adding more RAM?, or whether the RAM upgrade is a good value?, etc.

We need to be clear in delineating what is "fact" and what is "opinion".
 

motrek

macrumors 68020
Sep 14, 2012
2,317
118
But you can upgrade your MBA ram later if 4GB isn't enough right?

/sorry, couldn't help myself
You can upgrade it by selling it and buying another. If you buy a used MBA then the cost of the upgrade might not be any more than it would cost you to buy more RAM.
 

lynaris0

macrumors newbie
Feb 21, 2015
13
0
Is 4gb of ram enough for working with logic pro and video editing?
After reading this thread I am absolutely not sure on which version of the MBA 13" to get.
 

Meister

Suspended
Oct 10, 2013
5,455
4,265
Is 4gb of ram enough for working with logic pro and video editing?
After reading this thread I am absolutely not sure on which version of the MBA 13" to get.
I dunno about Logic, but with video editing it depends on the type of files you are working on and the extent of your editing. I have seen people edit professional commercials in Adobe Premiere on a MBA with 4gb RAM.
For video editing the CPU is usually your bottleneck.
 

dsmedic10

macrumors member
Feb 16, 2015
77
22
I've used a 2012 MBA 1.8/4/256 for Logic Pro with no problems at all. I run about 20-25 tracks in a project w a few effects and synths. I also record up to 8 tracks at a time using a TASCAM US-1800 (drum tracks) with no problems at all. No drop outs. No studders. No clips or other audio weirdness.
 

kage207

macrumors 6502a
Jul 23, 2008
961
8
Even if you page your memory, it isn't a bad thing because the SSDs are pretty much RAM but with a few extra circuits and gates for keeping storage when powered off.

Plus you can read and write to your SSD a ton and never use all the read and writes it has. So no, you won't even notice a big performance hit even if you do page to your drive.
 

Hieveryone

macrumors 601
Apr 11, 2014
4,152
1,476
USA
A ram thread. How original! It's what we've all been waiting for.
This made me lol.

This guy has a point when you open up activity monitor it actually shows it's using up a lot of RAM. But as everyone says, that doesn't mean anything. Still got plenty left.
 

Meister

Suspended
Oct 10, 2013
5,455
4,265
Even if you page your memory, it isn't a bad thing because the SSDs are pretty much RAM but with a few extra circuits and gates for keeping storage when powered off.
While you are right that ssds are much more similar to RAM than the old spinners, RAM is still faster than an ssd by a gigantic margin. Ssds cannot completely compensate for lack of memory, even though swapping is much, much less painfull than before.
 

kage207

macrumors 6502a
Jul 23, 2008
961
8
While you are right that ssds are much more similar to RAM than the old spinners, RAM is still faster than an ssd by a gigantic margin. Ssds cannot completely compensate for lack of memory, even though swapping is much, much less painfull than before.
No, but to the average user they won't notice it swap.