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32GB needed more than any other update
- Thread starter groverb
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I agree... I have had 16GB of RAM for over 4 years now... with many VM's, RAM is in short supply.
From what I understand there's nothing that can be done about it until the next generation of processors comes out. I'm sure Apple would love to sell more overpriced memory if they could. 
From what I understand there's nothing that can be done about it until the next generation of processors comes out. I'm sure Apple would love to sell more overpriced memory if they could.
Haswell quad core chips support 32GB of RAM.
I mean absolutely no disrespect when I say this but I consider myself a power user and my work requires me use parallels running between windows and OS X and I have at least a dozen applications open at any given time but what do people use that much ram for? I'm just genuinely curious.
Multiple VM's at once. Win 7, 8 and 10 run like donkey dung with anything less than 4GB allocated to them, XP is ok with 512MB although I usually give it 1GB. Now run them all at once. Bingo.
Are you sure? My understanding was that Haswell desktop chips do, but the notebook chips that Apple uses don't. In fact, I can't think of many notebooks that support 32GB of RAM at all, and the few that do are gaming machines or workstations that use desktop parts.
Virtual for sure, why do you need to run them in Real (physical)? Too much perf hit?
The problem is not CPU support but RAM availability. The biggest consumer RAM module is 4Gb (4 gigabit). To get 16GB, you need to use 32 of those modules, which is equivalent of two traditional RAM sticks. To get 32GB, you'd need to use 64 of them — these is simply no space for that. And nobody has been able to produce affordable 8Gb modules. There have been some attempts, but AFAIK, these never reached the market.
Of course, there are also other problems. As far as I understand, you will start getting diminished returns with 32Gb RAM fairly quickly on a consumer processor. The memory controller is simply not fast enough to efficiently work with this amount of RAM. CPU cache is also an issue.
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Why would you need to do that on your laptop? What is the application field?
I usually run a bunch of Linux VMs (db servers) + a Windows 7 VM + working on multi-GB datasets. Works just fine on a 16GB machine. A big problem with running that many active processes on your laptop is that it will absolutely kill your CPU cache and the performance will crawl down no matter how much RAM you have.
If you use your laptop to perform medical image based simulations/experiments using Matlab, Python etc., you can max out 32GB of RAM with just a few images or image volumes loaded.
True. But there is no need to load all the data at once if you use efficient algorithms, especially when you are already limited by computation capability of a laptop. So if you use a program that really needs everything in the RAM, its first and foremost a software design flaw. And besides, if you do those kind of things, you really need a supercomputer. Our university has a machine with 4TB RAM for stuff like that.
Again, I work with fairly big data myself, and I see little practical need for a laptop user to have that much RAM. What I mean is certainly not that '16GB is enough', but that for certain tasks, you really should use heavy cavalry (workstations/supercomputers). Tasks that require a lot of RAM will also require more processing power/more RAM controllers etc.
I had an HP laptop with 2GB, and it handled all kinds of stuff, (I practically abused that sucker.) I now have 16GB, and honestly I don't know if I will actually use more than 6, (if that) and I render, use, and make HD files (videos, music, and photos.)
What are y'all doing that uses up 16GB of RAM. Do you render 8k videos while having 5000 Chrome tabs open and 12 different OS systems installed? lol
... But really if Apple offered 32GB, I'd do that as it would be cool. Mainly I'd do it to further future proof my already futurized machine, ha ha.
I wonder if a "personal" home computer needs it though, wouldn't it be more appropriate for government, medical, scientific research, and large tech companies?
Kal.
What are y'all doing that uses up 16GB of RAM. Do you render 8k videos while having 5000 Chrome tabs open and 12 different OS systems installed? lol
... But really if Apple offered 32GB, I'd do that as it would be cool. Mainly I'd do it to further future proof my already futurized machine, ha ha.
I wonder if a "personal" home computer needs it though, wouldn't it be more appropriate for government, medical, scientific research, and large tech companies?
Kal.
Haswell mobile CPUs will support 32GB
The Haswell CPUs used in rMBP 15 will support 32GB RAM, but the lack of 16GB SO-DIMMs means that this normally means 4x8GB modules. There are 15" laptops that support this (HP and Lenovo have workstation laptops with 32GB), but Apple has never opted for more than 2 SO-DIMMs in their laptops.
I often use the 16GB in my rMBP 15, but seldom think I would require 32GB, mainly because I don't run multiple VMs simulatanously - occasionally I will run two large Linux VMs, (app servers + Database), but I feel that this will probably use all my CPU capacity as well (2-3 vCPU each VM, leaving a single core for the host OS).
To have more VMs, and require more RAM, I feel you also need more CPU power than available in a quad-core mobile chip. I do have a quad-core desktop Xeon E3 workstation with 32GB, and this feels about right. I can comfortably run multiple VMs on this machine. If I had 6, 8 or more cores, I'd want to increase the RAM, and would be looking at Xeon E5s with 64-128GB RAM. At present I don't need this - and it would cost a lot!
The Haswell CPUs used in rMBP 15 will support 32GB RAM, but the lack of 16GB SO-DIMMs means that this normally means 4x8GB modules. There are 15" laptops that support this (HP and Lenovo have workstation laptops with 32GB), but Apple has never opted for more than 2 SO-DIMMs in their laptops.
I often use the 16GB in my rMBP 15, but seldom think I would require 32GB, mainly because I don't run multiple VMs simulatanously - occasionally I will run two large Linux VMs, (app servers + Database), but I feel that this will probably use all my CPU capacity as well (2-3 vCPU each VM, leaving a single core for the host OS).
To have more VMs, and require more RAM, I feel you also need more CPU power than available in a quad-core mobile chip. I do have a quad-core desktop Xeon E3 workstation with 32GB, and this feels about right. I can comfortably run multiple VMs on this machine. If I had 6, 8 or more cores, I'd want to increase the RAM, and would be looking at Xeon E5s with 64-128GB RAM. At present I don't need this - and it would cost a lot!
Across four slots. They'd need to re-engineer the logic board for double the amount of "slots" rather than just dropping in higher density RAM.
The only way of getting 32GB into the ThinkPads at work is with four memory modules, which are only enabled on the quad core CPUs. The dual core machines have blanks installed.
Spec sheet for the CPU in that machine : http://ark.intel.com/products/85212/Intel-Core-i5-5200U-Processor-3M-Cache-up-to-2_70-GHz
It seems i7 would be an option but not available yet.
Anyway, at 1.8Kg, I think this is the lightest 32GiB laptop now. Normally it was a ThinkPad at 2.6 or 2.7Kg, AFAIK.
At least advertised, one might be able to put 32GiB of Intelligent Memory in a lighter Broadwell laptop.
When that ThinkPad is updated to Broadwell, it might support 64GiB, at least unofficially.
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32Gb and a dual-core CPU with 3MB cache
That reminds me of all those cheap GPUs that advertise with 4Gb DDR3 RAM
Why not setup a free ESXi system loaded up with RAM and offload the VM load there? I have 4 VMs running on a VMWare server at work. The newest version of Fusion lets you open console connections to VMs running on ESXi and the quality is better than any screen sharing app I have ever used and you have on demand access to whatever VM you need without the hit on your local machine.