Re: RPI3, heatsinks, throttling

[Emilian Bold <emilian.bold%gmail.com@localhost>]

I wonder if the OS does any throttling on the RPI or if it's perhaps
handled by the Broadcom hypervisor.

I have never put heatsinks on my RPIs but I also didn't use them as build
server or something very CPU intensive.

Still, I don't expect to be able to fry them -- they should at least
auto-shutdown, no?

--emi


On Sat, Jul 7, 2018 at 6:39 PM, Greg Troxel <gdt%lexort.com@localhost> wrote:
>
> I am curious about the RPI3 in a normal top/bottom case, and the
> necessity/wisdom of heatsinks, and I don't see anything in the netbsd
> wiki page.
>
> Reading a bunch, it seems that putting a CPU heatsink on reduces the
> temperature for a given workload, but does not entirely obviate the need
> for throttling the CPU.
>
> I wonder if NetBSD -8 and -current will actually drop CPU speed back
> automatically due to high temperatures?
>
> Have people seen this happen?
>
> Is it sufficient to protect the system?
>
> Is it sane to run MAKE_JOBS=8 on a RPI3?  With or without a heatsink (in
> a case)?
>
>
> Some data from idle systems (both 8.0_RC2, indoors):
>
> RPI1 without heatsink:
>                  Current  CritMax  WarnMax  WarnMin  CritMin  Unit
> [vcmbox0]
>   temperature:    43.312   85.000                             degC
>
> RPI3 with heatsink:
>                  Current  CritMax  WarnMax  WarnMin  CritMin  Unit
> [vcmbox0]
>   temperature:    51.540   85.000                             degC