"Unable to request 2 buffers: Cannot allocate memory" with 2 64mp cameras

Thanks Henri!

Just FYI - I have been testing full resolution of the OV64A40 64 MP sensor with two cameras at the same time on RPi 5 8GB.

It seems to be working most of the time without any memory issues at full resolution.

I can see memory usage increases by 1.6 GB when the cameras take photos. But other than that, it appears to be working.

I do get several errors sometimes that I am still working out here: Device or resource busy and other errors OV64A40 B0483 - #2 by wallarug

that is very interesting. i also have pi 5 8GB but i have been away from active development for a month

can u do

uname -a

and paste it here to tell me your kernel version

and do

libcamera-still --version

to let me know of your libcamera version. the pi5 is using IOMMU that can potentially map entire 8GB RAM for device memory. im not sure it was in use though in kernel version that i have.

Also are you using lite or desktop version of PI OS?
And which tool are you using to notice that 1.6GB memory spike while taking pictures?

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Hey Henri,

I’m using the Raspbian Server edition / lite (official) without a desktop environment (from memory). From March 2024.

uname -a

Linux cscs-0002 6.6.20+rpt-rpi-2712 #1 SMP PREEMPT Debian 1:6.6.20-1+rpt1 (2024-03-07) aarch64 GNU/Linux

libcamera-still --version

rpicam-apps build: 414a7383464b 18-04-2024 (13:56:48)
libcamera build: v0.2.0+120-eb00c13d

I have been watching htop to determine memory changes.

I really want to get to the bottom of this. I want the cameras to be reliable.

the cameras are reliable. its just that at max res 64mp with rgb888 theres some sort of issue. based my research and info i got from @Dion i concluded that this is some soft of libcamera issue because @Dion told me that arducam is working with libcamera people to resolve this.

and based on your info i can confirm i indeed have older kernel and libcamera versions. also im running regular lite not server version.

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My problems persist at 16MP and 64MP.

Would be interesting to hear Dion’s views on this a few months down the track.

whats your problem at 16MP. are you displaying video from two cameras at the same time?
is 48MP ok?
did you try 64MP yuv420?

I haven’t tried 48 MP since that is not the same full sensor crop.

I am using yuv420 (I worked out last night) because the default of libcamera-still is this format when you save the image as .jpeg.

The problems are outlined here: https://forum.arducam.com/t/device-or-resource-busy-and-other-errors-ov64a40-b0483/