I usually surf with multiple tabs open, stream video and maybe have the odd app open. My activity monitor says I'm using 9gb of ram. I'm glad I've updated my memory from 8gb to 16gb. I'm not sure if I need more or I'll ever need more of if more will improve my performance in any way.
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Who has 32GB RAM in their iMac?
- Thread starter stevefo
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Note that OS X will attempt to use all the memory you have. Any not needed by the OS or applications will be used for disk caching or as "compressed" to hold applications that are no longer running but can be expanded when needed (faster than disk access). Since the reported Memory Used = App Memory + Wired Memory (which is basically system memory) + File Cache + compressed, that figure should be nearly equal to Physical Memory on any machine. To determine the amount of RAM you are actually using, add App Memory to Wired Memory. Examples:
1. Server computer which has been running 25 days shows that 7.99 out of 8.00 GB RAM used, however only 4.53 GB is actually in use. Never swapped (which is generally bad for performance).
2. My iMac shows 7.6 of 8 GB RAM used, but only 4.87 is in actual use. It's currently running Safari, Screen Sharing, Skitch, Mail, Activity Monitor, CrashPlan, ScanSnap, Text Expander, DropBox, Hazel, Alfred, BetterTouchTool, ShouldISleep, and DragonDrop.
3. Entertainment Center shows 3.81 of 4.00 GB used but is only using 1.92 GB. At some time in the past swapping occurred (it's been up 28 days).
Notice that the "Memory Pressure" of all three systems is in the Green.
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It's well worth it if you have the Adobe master collection and/or a DAW like logic for music production (Like I do), these programs ARE memory intensive so 32gb of ram means you can have any combo of these apps open and you won't notice any sluggishness from your mac.
I have 32 gb and cant wait for next imac to get out so I can get 64gb (my current 5k imac only support 32 gb). Since I work a lot with adobe programs and game engines and 3d programs (AE, Photoshop, Unity, Unreal, Zbrush) I need a lot of memory. Currently my biggest issue though is throttling. I saw videos that this is much better in the current 2015 iMac, but the changes in general isn't big enough to justify buying the 2015 iMac now.
I think it's Yes and No.
More RAM itse;f won't make the OS run faster.
A 8G system can run as fast as the 32G system. However, for modern OS, more RAM usually help by using the extra RAM as cache.
Here are 2 examples
My Mac has 48G of RAM. By checking the Wired Memory, that almost never use more than 4G, and usually around 3G. That means the system itself can work fine with just 4G memory.
However, on the upper screenshot, my Mac can use more than 36G of RAM when I am doing some video editing, with another video encoding + some normal stuff (email, Safari, etc) in the background. That means my system really take the benefit of more than 32G of RAM, if I have anything less than that, memory compression or swap will be required. Furthermore, the system can using the remaining 11G RAM as cache, that will further speed up the process, and all 48G is used.
In the 2nd screenshot. No video editing, but just some video encoding in the background when I am using my computer. So, memory used is just around 14G, however, the system can use > 20G or memory as cache to speed up the encoding process. End up still more than 32G memory being utilised.
Of course, not everyone have this kind of usage. However, what I want to point out is even though the application itself don't need that much memory (2nd screenshot), the system can still use the free memory as cache to further speed up the process.
Since the system won't "demand" the cache if no extra RAM available. Therefore, it may be a bit tricky to determine if a user can benefit by having more RAM by just looking at their current memory pressure/ usage.
I totally agree that if the memory pressure is still in green, then most likely nothing to worry about it. However, having more RAM could help some operation run faster, because now the application can store everything in the cache, but no need to go back to the HDD when it need the data.
IMO, what helps a lot is actually the SSD, it's so fast now, therefore even without cache, the process still won't significantly slow down by the HDD. And this could be very important to make the user feel that the system never slow down even it's tiny bit lack of memory to operate (small swap files required).
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Just finished installing it.
When I first got her, the boot up time was 17 seconds. Now it's 12 seconds.
It's definitely worth paying $171 for the upgrade.
$201 minus $40, sold the stock RAM.
Boot up faster with more RAM??? It's hard to believe. It should never happen, more RAM will need more time to initialise. May be you actually reset something (e.g. SMC) during the memory upgrade, which cause the faster boot time.
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Handbrake itself is not that demanding. However, if the user know how to use the advance option, that can make a big difference. Some encoding parameter can use much more memory then the others (e.g. 2 pass with high lookahead value).
Therefore, comparing the memory usage simply base on "I also use handbrake" can be quite meaningless.
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Pending on your industry/field you might need 32gb. For most people its overkill, but its nice to have so your computer stays relevant longer.
Or you can have 32gb and use 16GB of it as a ramdisk >
I've try that. In general, not a good practice now. The modern OS use idle memory very well as cache. Create RAM disk will only avoid the system use them as cache. Of course, if the user want few GB very fast storage to work on (e.g. some small media editing job), RAM disk is a fantastic idea.
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2011 iMac just upgraded from 16 to 32 recently. I only did it because Sketch (a tool for work) would eat up a lot of ram very quickly. 32 is a bit overkill but it was the only option up from 16.
Um.... Not challenging you but is 3x8 = 24G a possible solution between 16G and 32G?
Not ideal of course, but possible, right?
I am just thinking 32G may not be the ONLY option after 16G.
Wired memory is memory reserved by the kernel. Applications use additional memory.
I have 24 GB installed.
I'm using 15.50 GB App Memory + 1.96 GB Wired Memory. In addition 2.94 GB is being used for cacheing files.
I don't use Photoshop. I hear it's often described as a memory hog.
Apparently this is what Activity Monitor looks like when Photoshop benefits from having enough memory.
See how Photoshop is actually grabbing 40.29 GB? See how the Memory Used is 63.37/64 GB?
Now, photoshop might actually be a special case, but frankly, if the only way you can use up your memory is by keeping all your applications open, I don't think there's going to be any performance benefit. (Few programs will trade space for time, it seems)
(Today I actually ran out of memory trying to ftp a very large file ( a few hundred megabytes) with Safari. My machine slowed to a crawl. Do I think I need more memory? No. In fact, I think I should try to avoid triggering memory leaks in Safari.)
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Agree, that's why I said 4G is good enough for the "SYSTEM" itself. On top of that, we need more RAM for applications.
However, how much is enough is very personal. I prefer to keep everything open, because I have plenty of stuff working in the background. Even my Safari is working on something with flash in the background, close them is not an option for me. And 2 accounts are always logged in on my Mac. I don't want to close my wife's account's applications either. Therefore, I prefer to have more RAM.
But for general use, if no need to keep all apps open in the background. I agree that's not a good practice to keep them open but run in low memory (or install more memory just for that).
Ya, I'm still stuck in the old days when u should always install even number of ram sticks for dual channel. im sure the performance benefits r minimal if any, but I'm OCD like that
I've got 32 GB of RAM in each of my iMacs. I do computations that take quite a bit of RAM, so it is helpful to have the extra RAM in my desktop. (I use servers for computations too, when I need much larger computing power.) It used to be beneficial to buy the Mac Pro for such purposes, but the iMac is more than sufficient for me now.
Just this week I upgraded the RAM in my brand new late 2015 5k iMac to 32GB. When I was looking at the options there were two different kits available:- 4 x 8GB (1867MHz) and 4 x 8GB (2133MHz). I went for the 2133 MHz (obviously) and it didn't work (see thread here). It may have been a bad batch I dunno but I know there are plenty of users on here that have this spec RAM running fine in their machines. I sent it back and got the 1867MHz and this works fine. My previous mac was a mid 2007 20" iMac so the difference in overall speed and performance between the machines is night and day
I then read the post above and started to wonder:- If RAM supposedly does not improve speed then why do manufacturers (Kingston in my case) sell the "faster chip"?
Unless you're using something that consumes a lot of RAM, in my experience
4 GB -> 8 GB = big difference in general use (browsing, random "Stuff")
8 GB -> 16 GB = maybe 10% difference in responsiveness due to being able to hold more in cache.
Tested with a hard drive.
if you've got SSD, the speed of your storage will mask some of the problems with not enough memory - and you'll probably notice very little difference between 8 GB and 16 GB in "general" use.
32 GB, unless you're running some apps that deal with large amounts of data is probably overkill. But RAM is cheap now, so...
In terms of cost vs. RAM size, i'd say that 16 GB is currently the sweet spot on a portable with only 2 slots - if you've got 4 slots (e.g., an iMac) 32 GB isn't expensive.
And yes, once you have "enough" RAM it is very much a case of diminishing returns - your mac will attempt to use excess RAM for disk cache, but as above if you're on SSD, the access to that is pretty fast anyway. And cache is a case of diminishing returns. The whole of OS X is less than 20 GB and the vast majority is stuff people never use, so once the entire operating system is cached in RAM there's no other way the Mac can make use of any more unless you're working with HUGE data sets.
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I see a lot of people posting about VMs. Yes, thats one of the use cases for a lot more RAM. I'm just waiting on the price of desktop PC motherboards that can take 64 GB to come down so i can simulate a vSphere cluster in VMware Workstation on my PC, but that's a bit of a niche use case. For most people 8-16 GB is plenty
4 GB -> 8 GB = big difference in general use (browsing, random "Stuff")
8 GB -> 16 GB = maybe 10% difference in responsiveness due to being able to hold more in cache.
Tested with a hard drive.
if you've got SSD, the speed of your storage will mask some of the problems with not enough memory - and you'll probably notice very little difference between 8 GB and 16 GB in "general" use.
32 GB, unless you're running some apps that deal with large amounts of data is probably overkill. But RAM is cheap now, so...
In terms of cost vs. RAM size, i'd say that 16 GB is currently the sweet spot on a portable with only 2 slots - if you've got 4 slots (e.g., an iMac) 32 GB isn't expensive.
And yes, once you have "enough" RAM it is very much a case of diminishing returns - your mac will attempt to use excess RAM for disk cache, but as above if you're on SSD, the access to that is pretty fast anyway. And cache is a case of diminishing returns. The whole of OS X is less than 20 GB and the vast majority is stuff people never use, so once the entire operating system is cached in RAM there's no other way the Mac can make use of any more unless you're working with HUGE data sets.
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I see a lot of people posting about VMs. Yes, thats one of the use cases for a lot more RAM. I'm just waiting on the price of desktop PC motherboards that can take 64 GB to come down so i can simulate a vSphere cluster in VMware Workstation on my PC, but that's a bit of a niche use case. For most people 8-16 GB is plenty
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I had 32gb in my 21.5" iMac but repurposed an 8gb stick into a Mac Mini so now it's a bit spartan with only 24gb. No noticeable difference in speed. What I did notice is that the more memory you have then the longer it takes to notice memory leaks slowly gobbling the free memory causing compression then swapping. I've seen a dirty big itunes memory leak and Chrome leak recently chewing up insane amount of memory.
I just installed 32 GB in my late 2015 Retina iMac. More memory does help at times, especially when running VMs, and although I could get by with 24 GB instead, 32 GB is a reasonable max for several years to come.
![32 GB.png]( "32 GB.png")
I currently have a late 2014 retina iMac 4.0GHz i7, AMD Radeon M295x, and 1TB Fusion Drive.
When I originally ordered it, I only upgraded it to 16GB of RAM because the additional 16GB was so expensive at the time ($600).
Fast forward to this week when I finally ordered the other two 8GB sticks from OWC for $100.
Installation was easy, and without performing measurements, it *seems* faster for heavy tasks such as running 3 different VMWare environments at the same time (Win10 bootcamp, Win7, Chromium) along with MS Outlook and iPhoto without any writing to the page file. Matter of fact, according to Activity Monitor, that most RAM used was 13GB. Everything was so quick as to seem that it would have been just as fast as running only one of those applications on the system.
I should have tried to run the above applications with only 16GB of RAM in order to see if I actually needed anything additional. However, Im too lazy to remove the new sticks in order to test it out. In any event, the $100 spent makes me happier knowing that I have that horsepower, even if Im not using it. Sort of like upgrading an engine when buying a car. 4cylinder sucks, 6cylinder is good, and while 8cylinder is awesome, it costs more and doesn’t get you there any faster if following the law.
When I originally ordered it, I only upgraded it to 16GB of RAM because the additional 16GB was so expensive at the time ($600).
Fast forward to this week when I finally ordered the other two 8GB sticks from OWC for $100.
Installation was easy, and without performing measurements, it *seems* faster for heavy tasks such as running 3 different VMWare environments at the same time (Win10 bootcamp, Win7, Chromium) along with MS Outlook and iPhoto without any writing to the page file. Matter of fact, according to Activity Monitor, that most RAM used was 13GB. Everything was so quick as to seem that it would have been just as fast as running only one of those applications on the system.
I should have tried to run the above applications with only 16GB of RAM in order to see if I actually needed anything additional. However, Im too lazy to remove the new sticks in order to test it out. In any event, the $100 spent makes me happier knowing that I have that horsepower, even if Im not using it. Sort of like upgrading an engine when buying a car. 4cylinder sucks, 6cylinder is good, and while 8cylinder is awesome, it costs more and doesn’t get you there any faster if following the law.
I just ordered 32gb of RAM from amazon for $240 CAD taxes in for my 2014 rImac
I don't think I need 32GB of ram but I was going to upgrade eventually anyway and it was a decent price.
I've got 32 in my 2011 iMac which I used for running multiple VMs. I've now got a Xeon server picking this up so really don't need it anymore. That said, the 5 year old machine is still great to work on!
I did the same as 59Burst. With my old iMac, 24GB was enough, and it is cheap to grab a couple 8GB DIMMs (in comparison to the cost of the iMac).
I did the same with the 2015, and if it does prove to not be enough for any reason, then I'll revisit and jump to 32.
I did the same with the 2015, and if it does prove to not be enough for any reason, then I'll revisit and jump to 32.