I used am trying to verify the different available memory between the older B board with 256mb RAM and the new 'b' revision board with 512mb... I am using the same 2012-10-28-wheezy-raspbian image...
I used top to view to identify system memory
top - 20:10:35 up 2:24, 2 users, load average: 1.02, 0.82, 0.63
Tasks: 89 total, 1 running, 88 sleeping, 0 stopped, 0 zombie
%Cpu(s): 1.7 us, 1.7 sy, 0.0 ni, 96.7 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
KiB Mem: 189104 total, 164028 used, 25076 free, 19484 buffers
KiB Swap: 102396 total, 0 used, 102396 free, 57200 cached
If I interpret this correctly, it shows a total memory size of 189.1mb... I get the same results with either board.
Is there a different command that will show the actual memory available as close to 512mb?
Re: Comparing memory beween 256k and 512k board
After posting my original comment and question, I created a new Linux image on another SD card. I then configured it on the 512mb board. Once I completed the configuration process and rebooted, I ran top. It now recognizes 448996kb RAM. lshw also reports 438mb memory.
So, this leads me to believe that the Linux image will attempt to allocate as much memory as is available when you initially configure the SD card on the Raspberry Pi board. It senses the available memory of the board you installed it on and partitions memory accordingly. If you move the SD image to another board, with more RAM, it will not recognize or make that additional memory space available automatically.
So, this leads me to believe that the Linux image will attempt to allocate as much memory as is available when you initially configure the SD card on the Raspberry Pi board. It senses the available memory of the board you installed it on and partitions memory accordingly. If you move the SD image to another board, with more RAM, it will not recognize or make that additional memory space available automatically.
Re: Comparing memory beween 256k and 512k board
...and I find that it does things in quite the opposite order...
When I put the SD card from my rev. 1 Pi into the rev. 2 Pi, it shows much more than 256MB free memory. This implies that it is keeping a constant amount of GPU memory. I do not know if this is right or wrong at this time.
When I put the SD card from my rev. 1 Pi into the rev. 2 Pi, it shows much more than 256MB free memory. This implies that it is keeping a constant amount of GPU memory. I do not know if this is right or wrong at this time.
Re: Comparing memory beween 256k and 512k board
In the newer versions of Raspian..... memory is allocated to the GPU by added (not included by default) the settings:
gpu_mem_256=XX
gpu_mem_512=XX
If you have a 256mb board, it will follow the gpu_mem_256 entry, 512mb the gpu_mem_512 entry.
You can allocate as little as 16
Ref:
http://elinux.org/RPiconfig#Memory
The default memory allocated to the GPU with no configuration entries is 64
gpu_mem_256=XX
gpu_mem_512=XX
If you have a 256mb board, it will follow the gpu_mem_256 entry, 512mb the gpu_mem_512 entry.
You can allocate as little as 16
Ref:
http://elinux.org/RPiconfig#Memory
The default memory allocated to the GPU with no configuration entries is 64
Dweeber A.K.A. Kevin...
My RPI Info Pages including Current Setup - http://rpi.tnet.com
My RPI Info Pages including Current Setup - http://rpi.tnet.com