Re: RPi 4 build time

From: Mark Millard via freebsd-arm <>
Date: Fri, 21 May 2021 22:13:01 UTC

On 2021-May-21, at 14:45, Evgeniy Khramtsov via freebsd-arm <freebsd-arm at> wrote:

>> World built in 22491 seconds, ncpu: 4, make -j4
>> 6 hours 45 minutes
> This is impressing considering that one old Athlon 64 space heater took more
> than 9 hours to build FreeBSD 12 in 2017 when CC=cc, LD=ld matched the src tree.

I probably should have noted that to use:


reliably, I also use:


(I've not tried to identify the minimum, just a
sufficient figure.)

I'll also note that:

documents in its note 2 that: "Warranty bit is never set on Pi4."
So, even more extreme combinations of force_turbo=1 and over_voltage
would not invalidate the warranty.

The 7 or so RPi4B's that I've had access to (four 8 GiByte, the rest
4 GiByte) all worked well with the combination indicated. I've not
tried to optimize to individual machine limits.

Mark Millard
marklmi at
( went
away in early 2018-Mar)