shalo
Posts: 74
Joined: Tue May 08, 2012 7:25 pm

240mb/16mb split

Fri Jul 27, 2012 6:44 pm

I can't find this mentioned anywhere, so I thought I would point out that it now appears to be an option to use 240/16. My pi has been running fine with it. https://github.com/raspberrypi/firmware ... aster/boot

The arm240_start.elf is automatically downloaded and available if you have used rpi-update.

mrlinux2u
Posts: 214
Joined: Sat Sep 24, 2011 8:38 pm

Re: 240mb/16mb split

Fri Jul 27, 2012 10:30 pm

Very cool indeed (and handy for headless servers), never noticed it when I ran rpi-update last night,just set it up now :)

Thanks for the heads up!!!

dom
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 5380
Joined: Wed Aug 17, 2011 7:41 pm
Location: Cambridge

Re: 240mb/16mb split

Fri Jul 27, 2012 10:38 pm

Yes, I spent a while tweaking the build options to free up some memory.
Note: there is not a lot of free memory on GPU, so it may be possible to cause problems by provoking memory allocation on GPU.

There's no 3D or H264 in the build, so that should just file. Playing audio and changing framebuffer size/depth (i.e. with fbset) can cause allocations, so that's the sort of thing that could fail.
Please test, and report any problems.

If it works fine, then the 224M split will be deprecated, as there's not much point in it (it has 3D and H264 support built in, but there's not enough memory for buffers to be allocated).

User avatar
aquarat
Posts: 73
Joined: Thu Jul 26, 2012 2:32 pm
Location: Cape Town, South Africa

Re: 240mb/16mb split

Sat Jul 28, 2012 5:57 pm

I don't have a display connected and I'm not running a GUI desktop... so this is particularly useful for me. Thanks :)
EOF

SirLagz
Posts: 1705
Joined: Mon Feb 20, 2012 8:53 am
Location: Perth, Australia
Contact: Website

Re: 240mb/16mb split

Tue Jul 31, 2012 2:52 pm

I've updated my ram selector script for the people who don't use raspi-config script.
Linky - http://sirlagz.net/?p=557
My Blog - http://www.sirlagz.net
Visit my blog for Tips, Tricks, Guides and More !
WiFi Issues ? Have a look at this post ! http://www.raspberrypi.org/phpBB3/viewtopic.php?f=28&t=44044

lb
Posts: 263
Joined: Sat Jan 28, 2012 8:07 pm

Re: 240mb/16mb split

Tue Jul 31, 2012 2:56 pm

How much free RAM does the 240/16 split have for the framebuffer? It would be great to still have a somewhat high-res framebuffer.

dom
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 5380
Joined: Wed Aug 17, 2011 7:41 pm
Location: Cambridge

Re: 240mb/16mb split

Tue Jul 31, 2012 3:34 pm

lb wrote:How much free RAM does the 240/16 split have for the framebuffer? It would be great to still have a somewhat high-res framebuffer.
1920x1200x16bpp is fine.

I wouldn't recommend 32bpp at that resolution, although it does seem to initally work. You may find some operation that allocates GPU memory (e.g. audio) will fail.

AndrewJohnson
Posts: 21
Joined: Mon Jul 30, 2012 7:34 am
Location: Derbs UK

Re: 240mb/16mb split

Mon Aug 06, 2012 9:44 am

Thanks - this is useful for headless pi-ers - like me!

240 MB of RAM is "as much as anybody would need" :roll:

kermitas
Posts: 108
Joined: Thu Jan 26, 2012 11:49 am

Re: 240mb/16mb split

Fri Aug 10, 2012 8:14 pm

AndrewJohnson wrote:Thanks - this is useful for headless pi-ers - like me!

240 MB of RAM is "as much as anybody would need" :roll:
I have just discovered this new possibility :).

From 220 MB ('total' showed by 'free' command) now I have 236 MB :).

kermitas
Posts: 108
Joined: Thu Jan 26, 2012 11:49 am

Re: 240mb/16mb split

Fri Aug 10, 2012 8:23 pm

kermitas wrote:
AndrewJohnson wrote:Thanks - this is useful for headless pi-ers - like me!

240 MB of RAM is "as much as anybody would need" :roll:
I have just discovered this new possibility :).

From 220 MB ('total' showed by 'free' command) now I have 236 MB :).

One more thing. I am using USB webcams with rpi (accesing them via uvcvideo / v4l or v4l2).
Rpi is completly headless, I'm just producing tons of *.JPG files.

For capture I am using 'motion' or 'fswebcam' - generally I'm using programs that are based on v4l and /dev/videoX (/dev/video0, /dev/video1, ...).

Now I set 240/16 memory split but I started to have doubts if it will work stable for me...

How do you think: could GPU and it's RAM be involved into image capture and/or JPEG compression process??

(If yes, is 16MB RAM for GPU enough for headless rpi that creates JPEG files in 1920x1080 using MJPEG palette [sometimes it is also called 'input type'] ??)

Thanks,
Arthur.

dom
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 5380
Joined: Wed Aug 17, 2011 7:41 pm
Location: Cambridge

Re: 240mb/16mb split

Fri Aug 10, 2012 9:06 pm

kermitas wrote:
Now I set 240/16 memory split but I started to have doubts if it will work stable for me...

How do you think: could GPU and it's RAM be involved into image capture and/or JPEG compression process??
No I don't think the RAM matters. The JPEG decode is not done on the GPU. But you can't be sure without testing. Try the 224 or 196 split and see if reliability improves.

mrlinux2u
Posts: 214
Joined: Sat Sep 24, 2011 8:38 pm

Re: 240mb/16mb split

Sat Aug 11, 2012 1:12 pm

hi,

I can confirm that motion works fine with the 240/16mb split and I've had no problems whatsoever with stability, and all in all the new memory split is very stable (not had any crashes etc since I installed it, and it's running 24/7 on two rpi's).

Cheers

mrlinux2u

kermitas
Posts: 108
Joined: Thu Jan 26, 2012 11:49 am

Re: 240mb/16mb split

Sat Aug 11, 2012 3:38 pm

dom wrote:No I don't think the RAM matters. The JPEG decode is not done on the GPU. But you can't be sure without testing. Try the 224 or 196 split and see if reliability improves.
mrlinux2u wrote:I can confirm that motion works fine with the 240/16mb split and I've had no problems whatsoever with stability, and all in all the new memory split is very stable (not had any crashes etc since I installed it, and it's running 24/7 on two rpi's).
Thank you gus for your answers.

I can also confirm now that for v4l (v4l2) and JPEG compression amount for GPU ram is not important. I tried 16MB and 64MB and in both scenarios all works the same.

Return to “Advanced users”