7GB memory in use, 8GB available

Discussion in 'MacBook Pro' started by TweakOnline, Apr 28, 2014.

  1. TweakOnline macrumors regular


    Dec 17, 2012
    Hi there,

    I've looked up my MacBook Pro 15'' Retina's activity log and I mentioned that it was using over 7GB of memory, yet the MacBook itself has 8Gb available. If I may believe activity log, over 4GB of memory was used by apps, 1.5GB was wired memory and the rest was cached.

    Is 4.5GB of usage normal for a standard Mac OS X Mavericks configuration? As I see right now, Safari takes only 300 Mb and Google Drive uses 'just' 150 Mb of memory. Over 1 GB is used by something called kernel task (don't know what it is). Does anyone know if this normal? Could it eventually slow down your Mac's performance?

  2. Hieveryone macrumors 68040

    Apr 11, 2014
    Same! By just using chrome and leaving mail and iMessage open I'm using something like 7.5-7.9 GB of memory!

    I'm so confused because it makes me wonder, how can someone then use 4GB of memory if browsing the web uses so much?

    I'm sure it's normal but I would like to know if others are experiences this like you and me.
  3. dmccloud macrumors 6502a


    Sep 7, 2009
    Anchorage, AK
    Assuming you're using Mavericks, you need to look at the Memory pressure graph, not the amount of RAM actually in use. As long as that graph (bottom center of the Memory tab in Activity Monitor) is green, you're fine.
  4. TweakOnline thread starter macrumors regular


    Dec 17, 2012
    Ah, then it should be alright! :) But doesn't this affect the battery life of my MacBook?
  5. snaky69 macrumors 603

    Mar 14, 2008
    Having more content in RAM has no effect whatsoever on battery life. RAM is always powered when the computer is.

    What that content is being used for is what'll affect battery life.
  6. 5to1 macrumors 6502

    Mar 9, 2008
    No, as snaky69 said RAM is always powered while the machine is on. Moreover, its the most power efficient and quickest access storage on the machine. Therefore, theres no power hit in leaving stuff cached in RAM and it also saves time and power to grab what you need from RAM rather then accessing other less efficient storage (especially a mechanical HDD, but even against an SSD).
  7. MartinAppleGuy macrumors 68020


    Sep 27, 2013
    You don't understand how to read RAM in OSX Mavericks. You are not taking into account RAM compression, App Cache, and RAM pressure. Here is an example:

    When having iMovie open with a large video, and Chrome with a 5-10 tabs, I am using 6Gb of my 8Gb of RAM. The system can then use another 2Gb before it hits the total, where is will start to clear App Cache, then another 2-3Gb (App Cache) before it starts compressing RAM, then another 4-6Gb before touching Swap (ie- ran out of RAM). So in this circumstance, using 6Gb of RAM is using 31.5% before I run out of RAM.

    If your RAM pressure is red and you are a Swap/Page-out larger than a few Kb then your Macbook has ran out of RAM. If it is green, and you still have a lot of cache left, you are using a tiny amount.

    With RAM compression, I had all of my applications open, iMovie doing some exporting, and 100 tabs split between Chrome and Safari (around 50/50 each) and I was using 15.14Gb of RAM with my 8Gb of RAM iMac . And it still never touched swap. And my RAM compression was green. This is due to the heavy caching OSX does (to make apps launch instantly, rather than fetching data from backing storage which is a much slower process) as well as RAM compression. RAM compression uses the WKdm compression algorithm allowing data held in RAM to be compressed and decompressed almost instantly meaning you can have a lot more running before you run out of RAM. As said above, I use using 15.15Gb of RAM (and my iMac has 8Gb). What this means, is that the data within RAM consisted of 15.14Gb (with some being compressed to make it fit on the 2X4Gb modules, but then instantly decompressed when needed).

    Another thing to note, is that when I was using this much, my iMac was still very responsive (90% as responsive when compared to not pushing it). RAM pressure was also green, meaning I could push around 17Gb of RAM on my 8Gb system.

    I hope this has helped you understand how RAM works in Mavericks. When you see "Memory Used: 7.xx", don't just think you are using all of it. Look at App Cache then add that number on to your total RAM (i.e 7.xx out of 10/11Gb of RAM used, rather than 7.xx out of 8Gb used), then look at Compressed RAM and if 0 add 6Gb again on to your total. In the end, you are using 7Gb out of 17Gb. Also look at RAM pressure: green indicated you have loads of free RAM, amber indicated you are pushing the system RAM but there is still RAM free, and red indicated you have ran out of RAM and data has to be swapped to disk.
  8. Meister Suspended


    Oct 10, 2013
    Memory graph green = :)
    Memory graph yellow = :(
    Memory graph red = :mad:

    Same as traffic light.

    I agree though that mavericks is still displaying to many numbers and words. they need to dumb it down more!
  9. Barney63 macrumors 6502a


    Jan 9, 2014
    Bolton, UK.
    I thought amber traffic lights meant put your foot down to get through lol

  10. Meister Suspended


    Oct 10, 2013
    Good point. Like I wrote:
  11. christarp macrumors 6502


    Oct 29, 2013
    Honestly it's not a big deal. What you really should be looking at is the graph as previously mentioned.

    Take a look at me trying to max out my ram here:


    Note: I was running all my software development stuff and two games at the same time to achieve this.

    You can see I'm using 7.99GB of memory out of 8, I should be out of ram yeah? Well not exactly. I have an entire 1GB of ram being compressed, that's a lot of compression! I also still have room that can be excavated via file cache if it needs to, and all while not using a single byte of swap file. The graph has risen, but still in the green, i'd be fine with even more ram being used right now.

    There's a lot of room for expansion in RAM, and the OS manages it beautifully on its own.
  12. Meister Suspended


    Oct 10, 2013
    I wanted to share an observation that noone here seems to have ever mentioned in these countless ram-threads.

    One thing that really does eat up a lot of ram, besides the use of VMs, is running two user profiles simultaniously.

    I use my rmbp for work and privatly and change between those two user accounts without logging out of them. That pushes the ram into the yellow zone sometimes. Properly logging out of the account you are not using solves this problem immediatly.

    Nevertheless, if you know that you will need to run them at the same time for some reason, then consider more ram at your next purchase.
  13. joejoejoe macrumors 65816

    Sep 13, 2006
    My understanding is that OSx is designed to always use as much RAM as it can

    As other's mentioned RAM is the quickest access point for info/storage on computer.
  14. simonsi macrumors 601


    Jan 3, 2014
    Might be better to say it makes the best use of all the RAM available, be that 4, 8 or 16Gb - and that means trying to have vital, useful or potentially useful stuff in it.
  15. TweakOnline thread starter macrumors regular


    Dec 17, 2012
    Thanks for your help, it helps me understand the way OSX works (and if I should add up to 16GB of ram at my next purchase :) ). Nevertheless, I also have a Windows computer with 12GB of ram, it uses about 3GB a day; the other 9GB is 'just there'. Theoretical OSX would launch apps a lot quicker when you have more ram available (in case you have a MacBook Air with 4GB of ram), but I think 8GB is enough to run Safari, Skype, Spotify, Dreamweaver and all other stuff together.

    I bet FCP needs a lot of ram, just like Adobe After Effects and Premiere (in Windows it does), so I will get that in mind with my next desktop- purchase.

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