FORUMS

Analysis & Opinion

Top Forum Discussions

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

2,529 posts
Thanks Meter: 523
 
Post Reply Subscribe to Thread Email Thread
4th February 2013, 08:00 AM |#11  
Junior Member
Flag Seattle
Thanks Meter: 0
 
More
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, 08:55 AM |#12  
Member
Flag Arles
Thanks Meter: 3
 
More
May be video ram is shared with main memory ?
4th February 2013, 09:00 AM |#13  
mieszk3's Avatar
Senior Member
Flag Poznan
Thanks Meter: 52
 
More
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, 09:19 AM |#14  
Junior Member
Flag Seattle
Thanks Meter: 0
 
More
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, 07:56 AM |#15  
JarGnex's Avatar
Senior Member
Thanks Meter: 10
 
More
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 06:40 PM.
19th February 2013, 02:00 PM |#16  
Senior Member
Flag Toronto
Thanks Meter: 259
 
More
thats seems to be a normal thing for 4.2.2
19th February 2013, 02:03 PM |#17  
dibblebill's Avatar
Senior Member
Flag Raleigh, NC
Thanks Meter: 671
 
More
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, 10:42 PM |#18  
espionage724's Avatar
OP Senior Member
Thanks Meter: 523
 
Donate to Me
More
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.
The Following 2 Users Say Thank You to espionage724 For This Useful Post: [ View ]
19th February 2013, 11:57 PM |#19  
dibblebill's Avatar
Senior Member
Flag Raleigh, NC
Thanks Meter: 671
 
More
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.

Sent from my Nexus 10 using XDA Premium HD app
20th February 2013, 12:19 AM |#20  
IRX120's Avatar
Senior Member
Flag Atlanta
Thanks Meter: 653
 
More
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.

Sent from my Nexus 7 using xda app-developers app
20th February 2013, 03:27 AM |#21  
Senior Member
Thanks Meter: 787
 
More
Quote:
Originally Posted by IRX120

Odd, seeing as how the N7 has 975/1024 available
And my nexus 4 has 1.8 of the 2gb available.

Sent from my Nexus 7 using xda app-developers app

Doesnt Tegra3 have its own dedicated vram though?
Last edited by EniGmA1987; 20th February 2013 at 03:32 AM.

Read More
Post Reply Subscribe to Thread

Tags
memory, missing, ram

Guest Quick Reply (no urls or BBcode)
Message:
Previous Thread Next Thread
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes