Raspberry Pi is a Low-Power, Credit-Card Sized Computer

[Dirk Broer]

For those Raspberry Pi 5 and 4 users that do not follow Jeff Geerling or forums.raspberrypi.com too closely: free performance upgrades!

SDRAM Tweaks
To get the latest RAM speedups for now (this may be default soon):

1. Update the Pi's firmware to the latest version:

   sudo rpi-update

   (confirm with Y)
2. Edit the bootloader config:

   sudo rpi-eeprom-config -e

3. Add the configuration SDRAM_BANKLOW=1 (for Pi 5, you might also want to test SDRAM_BANKLOW=2 For Pi 4, use 3)
4. Reboot

NUMA Emulation
The needed patches required have now been added to the latest Raspberry Pi's OS kernel, so to use NUMA, all you have to do is make sure you're on the latest Raspberry Pi OS (Bookworm, not Bullseye!)

sudo apt update --fix-missing
sudo apt full-upgrade

To check if NUMA emulation is working, run

dmesg | grep NUMA

and make sure it says something like mempolicy: NUMA default policy overridden to 'interleave:0-7'

You can tweak the settings further if you want by adding numa=fake=[n] (where n is between 2 and 8) inside /boot/firmware/cmdline.txt, though the defaults should be appropriate for most use cases.

BTW: The Raspberry Pi 5 is now available in all the same various formats as the Raspberry Pi 4: SBC, Keyboard and Compute Module.