Hardware Reference
In-Depth Information
command. Hostnames should be unique, which can cause a problem if you have more than
one Raspberry Pi on your network. You can change a Pi's hostname at any time using the
Hostname option of
raspi-config
's Advanced Options menu, selected by highlighting it
with the cursor keys and pressing the Enter key.
When you access the Hostname setting,
raspi-config
will inform you of the rules of a
hostname. Because hostnames adhere to an international standard, known as a
request for
comments
or
RFC
, certain characters aren't allowed: a hostname should only contain letters
and numbers, and can include hyphens as long as they aren't at the beginning or end.
Confirm you've read this message by pressing Enter.
Using the Backspace key, delete the current hostname in the box that appears and type in
your new choice. You can opt for a descriptive hostname such as “living-room-pi” or name
your devices based on a theme such as “bladerunner” for science fiction films. When you
have chosen your name, press Enter to confirm. To exit
raspi-config
, press the Right
arrow key twice to highlight Finish and press Enter. You'll be prompted to reboot the Pi;
press Enter to confirm.
A3 Memory Split
Depending on your Raspberry Pi model, you will have either 512MB or 256MB of memory
available to the system. This memory is split between the BCM2835 chip's general-purpose
processor, known as the
central processing unit (CPU)
, and the graphics processor, known as
the
graphics processing unit (GPU)
. By default, 128MB of memory is reserved for the GPU
while the remainder is given over to the CPU.
If you're not using the graphics processor, such as when the Pi is used as a web server with no
display connected, you can reduce the amount of memory reserved for the GPU using the
Memory Split option in
raspi-config
. Highlight this option with the cursor keys and
press Enter to load the menu.
Using the Backspace key, delete the current value listed in the box that appears and enter a
new choice. The minimum you should give to the GPU to ensure proper operation is 16MB,
which should be entered simply as the number 16. If you have a Raspberry Pi model with
512MB of memory, you can increase the split to 256MB, which may improve performance
when using the GPU to render complex 3D scenes in games.
You can choose other values but you should restrict this to doubling the value at each step:
for example, 16MB can be increased to 32MB, 32MB to 64MB, 64MB to 128MB and so on.
