Benefit of 16GB of RAM

[avz]

I am wondering if anybody knows why going to About This Mac/Storage is so heavy on RAM usage? It is pretty much the only time when I see any memory compression and swap to the drive going on with 8 GB of RAM installed.

 

[cube]

Part of the rumors, or at least the wishful thinking from here, is expecting the 16.5" to be one class above the existing 15", which as you say is a series that has never been "workstation class". Some may say even the 17" series MBP wasn't either.

No Mac laptops, including 17".

 

[leman]

Part of the rumors, or at least the wishful thinking from here, is expecting the 16.5" to be one class above the existing 15", which as you say is a series that has never been "workstation class"

So far, there is zero evidence that Apple is making a laptop that can compete with 3-5kg workstation machines. People just see the 16" and jump to baseless conclusions. Not saying it's impossible, but what is the point in building up so much hype on an empty spot? Since MBP was first released, it was positioned as a jack of all trades multi-purpose laptop whose unique proposition is excellent balance between performance and portability. If the rumoured 16" is indeed some sort of larger laptop with a 100+Watt GPU, then it won't be a MBP anymore. My personal guess: it's just going to be a 2016 chassis with smaller display bezels. The current 15" form factor can easily fit an 16" display.

Some may say even the 17" series MBP wasn't either.

The 17" was just the 15" with bigger display and few extra ports. People who claim that 17" was a "workstation" have either very short memory or no clue whatsoever about the laptop market. Back in the 17" days, you could buy laptops with double amount the CPU cores and 4 times more RAM that were two times or more faster than fastest contemporary MBP. Now, the 2019 MBP is within 30% of fastest laptops (CPU-performance wise). Macs were never more performance-oriented than now. Yet people complain.

 

[cube]

Back in the 17" days, you could buy laptops with double amount the CPU cores

You could even buy 12-core Xeon laptops. But they weighed 5kg and the battery lasted half an hour.

They also came with a 300+ watts charger.

They should now make some 3950X laptops with Vega II Pro.

 

[richinaus]

So far, there is zero evidence that Apple is making a laptop that can compete with 3-5kg workstation machines. People just see the 16" and jump to baseless conclusions. Not saying it's impossible, but what is the point in building up so much hype on an empty spot? Since MBP was first released, it was positioned as a jack of all trades multi-purpose laptop whose unique proposition is excellent balance between performance and portability. If the rumoured 16" is indeed some sort of larger laptop with a 100+Watt GPU, then it won't be a MBP anymore. My personal guess: it's just going to be a 2016 chassis with smaller display bezels. The current 15" form factor can easily fit an 16" display.



The 17" was just the 15" with bigger display and few extra ports. People who claim that 17" was a "workstation" have either very short memory or no clue whatsoever about the laptop market. Back in the 17" days, you could buy laptops with double amount the CPU cores and 4 times more RAM that were two times or more faster than fastest contemporary MBP. Now, the 2019 MBP is within 30% of fastest laptops (CPU-performance wise). Macs were never more performance-oriented than now. Yet people complain.

Yes, the MBP simply was, is or never will be a workstation but a well balanced machine. I would say though that the integration of egpu certainly pushes it in that direction when used.

 

[leman]

Yes, the MBP simply was, is or never will be a workstation but a well balanced machine. I would say though that the integration of egpu certainly pushes it in that direction when used.

Yep, the eGPU is surprisingly viable. I just got one on sale last week (Vega 56 in a Razer Core X) and it works seamlessly. I can even use it in Bootcamp with internal display acceleration without any additional config whatsoever (thanks to the fantastic work of Mat of bootcampdrivers)

 

[pshufd]

I have two 2008 Dell XPS Studio desktops and they have Nehalem i7s and can hold up to 24 GB of RAM. They are surprisingly good systems, even today, outfitted with SSDs and a lot of memory. It would be great if they could run macOS. I paid $580 each for these systems - they were refurbs in 2009. I upgraded the PSU on both and have done other upgrades over the years.

 

[Howard2k]

I'm sorry but when you say the iPhone doesn't run MacOS, I don't think you know what you are talking about:

https://techcrunch.com/2017/10/01/apple-open-sourced-the-kernel-of-ios-and-macos-for-arm-processors/



The only fundamental difference between iOS and MacOS is the interface, but otherwise, both are running on the same base. Saying iOS is not MacOS is like saying Android is not Linux.

And no... the Mac is not supposed to "use" 16GB of RAM. That's like saying MacOS treats 16GB differently compared to 8GB. And even if that is indeed the case, that just proves my point even more: 16GB does in fact give a fundamental difference (i.e.: the OS treats it differently) compared to 8GB of RAM.

I'm quite aware of the shared foundation.

Of course macOS is designed to use RAM. MacOS will use spare memory for caching, for example. This can be seen in Activity Monitor. If you have a 16GB system with a very light workload and low memory pressure then the system will use that for caching data and this will improve performance. The OS knows how much memory it has and manages according to that. Yes, therefore it will treat 8GB differently to 16GB. And it will also treat 16GB differently to 32GB.

 

[pshufd]

I'm quite aware of the shared foundation.

Of course macOS is designed to use RAM. MacOS will use spare memory for caching, for example. This can be seen in Activity Monitor. If you have a 16GB system with a very light workload and low memory pressure then the system will use that for caching data and this will improve performance. The OS knows how much memory it has and manages according to that. Yes, therefore it will treat 8GB differently to 16GB. And it will also treat 16GB differently to 32GB.

I imagine that there are a huge number of other differences as well.

 

[Howard2k]

I imagine that there are a huge number of other differences as well.

My favourite part is that macOS and iOS are the same, but macOS cannot operate on 8GB whilst iOS can operate on 2GB. But they're the same.

 

[leman]

I imagine that there are a huge number of other differences as well.

AFAIK, iOS runs a monolithic kernel (no loaded extensions), has no swap, less services, has much stricter control over background processes and also has to deal with less concurrently active processes overall.

 

[pshufd]

AFAIK, iOS runs a monolithic kernel (no loaded extensions), has no swap, less services, has much stricter control over background processes and also has to deal with less concurrently active processes overall.

macOS is more like a server OS these days though a lot of things are turned off be default. The sharing options alone are substantial. I like the built-in VNC and FTP servers as examples. I'd guess that there is far greater device support given that you can hook up a very wide array of devices to a Mac while things are very limited on iOS.

Dealing with discrete GPUs is probably a lot more complexity as you have to deal with GPU switching.

There might be some things in the storage that are a lot more complicated as you have to deal with a much larger variety of device types.

 

[DeanL]

Unlike other people I won't get into the details but: I am a student (and have been forever...), and since 2012, I have always had 16 GB of RAM. In 2014, I bought a Mac with 8 GB and regretted it immediately. Went back to 16 GB ever since.
Being a student means I do a lot of research and constantly have multiple tabs open. Having 16 GB of RAM means there is no slow down because the memory is not compressed or sent to the swap space (which is the hard drive).

Now your biggest problem is that the RAM is not upgradable, which means if you make the wrong choice, you're stuck with it.
If you have the money, do it. If you don't, then don't do it.

 

[bill-p]

I'm quite aware of the shared foundation.

Of course macOS is designed to use RAM. MacOS will use spare memory for caching, for example. This can be seen in Activity Monitor. If you have a 16GB system with a very light workload and low memory pressure then the system will use that for caching data and this will improve performance. The OS knows how much memory it has and manages according to that. Yes, therefore it will treat 8GB differently to 16GB. And it will also treat 16GB differently to 32GB.

So does 16GB provide a benefit over 8GB?

AFAIK, iOS runs a monolithic kernel (no loaded extensions), has no swap, less services, has much stricter control over background processes and also has to deal with less concurrently active processes overall.

Not really. It just appears that way because you have no way to access the underlying components at stock.

Jailbreak the thing (basically just gain more administrative privileges) and it does act just like MacOS: you have access to and can load kernel extensions, which can bring back swap as well as the omitted services. You can also remove the restriction policies on background services, and ultimately, it already has support for concurrency and many other things. Heck, Apple's default apps rely on concurrency support.

Basically, the iPhone does in fact technically run MacOS under the hood. Steve Jobs was not lying.

But no, sadly, iOS does not "just work" with 2GB of RAM anymore. As development of the OS pushes on, it is catching up to MacOS in terms of RAM requirements.

There's a reason Apple has to outfit the new iPads with 4GB and 6GB of RAM now.

This fact both highlights how well designed Darwin is, and also how poorly coded Apple's platforms have become. Remember iOS 11?

 

[Howard2k]

So does 16GB provide a benefit over 8GB?

Yes, of course. And 17GB provides a benefit over 16GB. 18GB would provide a benefit over 17GB. 19GB would provide a benefit over 18GB. 100GB would provide a benefit over 99GB etc.


EDIT: for greater clarity, numbers are illustrative, not intended to be literal.

 

[leman]

Not really. It just appears that way because you have no way to access the underlying components at stock.

The point is that since iOS is locked, Apple can optimise the heck out of running kernel services, which reduces RAM requirements. And concurrency is one thing (of course modern ARM + iOS support and rely on it), I am talking about how much stuff actually has to be running in the background.

Jailbreak the thing (basically just gain more administrative privileges) and it does act just like MacOS

Jailbreak the thing and all bets are off. Its not about the OS capabilities, it's about how the OS and its services are configured. I mean, I could root into my router (it runs linux) and install all kinds of crap on it that will bog it down — it doesn't mean that the router does not have enough RAM, it simply means that I am messing with it.

Basically, the iPhone does in fact technically run MacOS under the hood. Steve Jobs was not lying.

Of course they do, most of this stuff is open source anyway.

There's a reason Apple has to outfit the new iPads with 4GB and 6GB of RAM now.

This fact both highlights how well designed Darwin is, and also how poorly coded Apple's platforms have become.

This highlights the fact that more and more demanding software is coming to the iPad. The base interface will have no problems running with 2GB. Once you get into all the photo editing software, no, 2GB is not sufficient anymore.

So does 16GB provide a benefit over 8GB?

Of course it does. Just at some point you won't see much difference (of course, depending on your user profile). Sure, the OS will aggressively preload stuff into RAM, but that is barely a reason to go for more RAM.

 

[cube]

Yes, of course. And 17GB provides a benefit over 16GB. 18GB would provide a benefit over 17GB. 19GB would provide a benefit over 18GB. 100GB would provide a benefit over 99GB etc.

Some of those increases can be detrimental depending on configuration and memory generation. A proper combination might not exist.

 

[Howard2k]

17GiB is a detriment unless you have 4 channels (8+4+4+1).

Right. My point was illustrative, not literal. I shall update.

Edit: updated. I hope that’s easier for you.

 

[cube]

Right. My point was illustrative, not literal. I shall update.

Edit: updated. I hope that’s easier for you.

And I edited my post because a proper 17GiB config could be possible in dual channel with DDR2 (8+8+0.5+0.5).

And there are no DDR4 modules smaller than 2GiB.

 

[Howard2k]

And I edited my post because a proper 19GiB config could be possible in dual channel with DDR2 (8+8+0.5+0.5).

Thanks. For sure memory should not be allocated randomly. It should be a considered deployment based on the optimal hardware configuration.