On September 20, 2021 1:03:39 PM UTC, Paul Wise <[email protected]> wrote:
>On Mon, Sep 20, 2021 at 9:19 AM LinAdmin wrote:
>
>> What I would like to see is that the official arm kernels
>automagically built by Debian could run unchanged on RaPi 32 & 64 bit.
>
>The RPi 4 is 64-bit, is there a reason for running a 32-bit Linux
>kernel?
yes: significantly reduced executable size, significantly reduced memory
footprint, resulting in better L1/L2 cache usage with consequent power
reduction.
the power consumption of the Cortex A53 compared to the Cortex A7 jumped TEN
PERCENT and that is down to 64 bit executables. to compensate, ARM now
recommends 50% larger L1 caches, which automatically come with an irrediemable
power consumption penalty even when running 32 bit binaries.
whilst everyone is rushing headlong into 64 bit in desktop and server land, the
abandonment is extremely alarming for the embedded world where power and
resources really matter, and can make the difference between a failed and a
successful product.
l.
