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[Q] Where's this 2GB of RAM at?

OP espionage724

4th February 2013, 09:00 AM   |  #11  
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Quote:
Originally Posted by bioorganic

I'm by no means an expert on this, but I dug into android memory management quite a bit when trying to optimize Shadowgun Deadzone performance. I don't think any of the apps measure memory used by native code. There's an adb command that will show you native memory use for an app, but I never dug that far into it. Again, I'm not a developer, but I assume your missing memory is being used by used by the parts android running native code. What's not clear to me is how android handles how much native memory an app can use. I got over my gaming fixation, but I'm still curious about this. If anyone can shed some light on this, I'd love to hear it.

I've checked /proc/meminfo and it looks like even the kernel doesn't see the full 2GB (assuming it is really there). MemTotal is 1,686,380 kB. Even if they were using 2GB==2,000,000,000 B, it's still missing over 150MB. I'd really like to know what is going on, but even Google support is completely clueless.
I'll probably just return it for something that lets me use the amount of RAM advertised.
4th February 2013, 09:55 AM   |  #12  
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May be video ram is shared with main memory ?
4th February 2013, 10:00 AM   |  #13  
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About 160MB is taken by Android OS (kernel + necessary libraries). It's reserved only for the OS, so it's unavailable for the user. It's common for all Android devices I've had.
For example my i9001 (SGS+) has also missing ~160MB of RAM (should have 512MB, but has only ~350MB available for apps.
4th February 2013, 10:19 AM   |  #14  
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If the video memory is shared at the hardware level, the number would make sense. What irks me is that I don't see that mentioned anywhere even on 'techie' blogs/reviews and even Google support doesn't know this about their device.
From what I understand, unless the kernel was modified to report less memory than is really available, meminfo should report the full amount accurately.
19th February 2013, 08:56 AM   |  #15  
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Re: [Q] Where's this 2GB of RAM at?

I don't even get 1.6 GB of ram
Sent from my Nexus 10 using Tapatalk 2
Last edited by JarGnex; 19th February 2013 at 07:40 PM.
19th February 2013, 03:00 PM   |  #16  
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thats seems to be a normal thing for 4.2.2
19th February 2013, 03:03 PM   |  #17  
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As an owner of a previous tablet, my Acer Iconia a500 reported (in 3.0, 3.1, 3.2, 4.0, 4.1, and 4.2) that it only had 725MB of RAM (it shipped with 1GB). My guess is that the missing chunk is graphics memory. I also show 1.6GB of RAM in my Nexus 10.
19th February 2013, 11:42 PM   |  #18  
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prior to 4.2.2, the GPU had 400-some MB reserved. At 4.2.2, there is almost an extra 400MB (386MB I think to be exact) reserved for the GPU, so 2GB - 800MB = 1.2GB

The extra GPU memory is to prevent userspace fragmentation if I read right.
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20th February 2013, 12:57 AM   |  #19  
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Re: [Q] Where's this 2GB of RAM at?
Awesome. Thanks for the explanation. I just noticed that after the CyanogenMod 4.2.2 patch, mine dropped as well. Honeycomb and Ice Cream Sandwich must've reserved around 256MB of memory.

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20th February 2013, 01:19 AM   |  #20  
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Re: [Q] Where's this 2GB of RAM at?
Odd, seeing as how the N7 has 975/1024 available
And my nexus 4 has 1.8 of the 2gb available.

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