
FreeBSD on the raspberry pi - zyngaro
https://github.com/freebsd/crochet/pull/140
======
anotherhue
I run FreeBSD and ZFS on my RPi-B as a cheap and cheerful destination for
remote zfs send replication.

I wrote up a guide: [https://github.com/hughobrien/zfs-remote-
mirror](https://github.com/hughobrien/zfs-remote-mirror)

~~~
forinti
Great job. How does it perform? I thought ZFS needed tons of RAM.

~~~
jacquesm
1G is not a lot of RAM?

~~~
forinti
Apparently, ZFS needs 1GB of RAM per 1TB of storage.

~~~
masklinn
You're probably thinking of deduplication (whose memory requirements is ~320
bytes per deduplicated block, and which generally requires way more than 1GB
per TB, it's highly variable depending on storage load but I've seen quotes
from 5 to 20GB/TB). Most users don't benefit from deduplication and it's
usually recommended not to enable it unless you do demonstrably get large
benefits from it (on FreeBSD, `zdb -S` will simulate and estimate
deduplication benefits).

1GB is the recommended conf for ZFS on FreeBSD, it will benefit from more (and
may need some tuning below 2GB) but even that's not a requirement, the FreeBSD
wiki's ZFS tuning page quotes "ZFS running nicely on a laptop with 768 Megs of
physical RAM" with tuning (and provides configuration values).

~~~
hengheng
I've always been wondering if file system RAM caches couldn't be moved to a
fast SSD nowadays. Do you think this would be possible with, say, an Intel
750?

~~~
masklinn
ZFS (and probably others) let you do that, kinda: it always has a primary in-
memory cache but you can add level 2 cache devices (L2ARC) to the pool. In
fact you can extend two different caches to storage devices: L2ARC is a _read_
cache, and you can add a separate set of Log Devices used by the ZFS Intent
Log, where _writes_ are cached.

------
xerography
The title of this post -- "FreeBSD on the raspberry pi" \-- is not very
descriptive. The title seems to imply that running on the Raspberry Pi is
news, which it's not, as myself or anyone else already running FreeBSD on our
Pi can attest to. I'd suggest changing the title to "Patch posted to have
FreeBSD use armv6hf target arch by default for the Raspberry Pi" \-- however,
someone just commented on the Pull Request:

>armv6 is already hard float, all armv6hf gives you is it will pass floating-
point data to functions in floating-point registers. I also expect that armv6
will be using the hard float ABI soon (within a month) an at this time armv6hf
will be removed.

So maybe just remove the post all together?

~~~
zyngaro
OP here I agree with you it can be misleading into thinking that FreeBSD is
_now_ available on the RPi which of course would be very misleading and simply
untrue because FreeBSD on the RPi is nothing new. Reading the others comments,
it's not misleading. Changing the title to what you have suggested would be
nice for the FreeBSD devs mailing list and would not appeal to many people on
HN. The point of the post is to draw attention to FreeBSD on the RPi and
FreeBSD as it's really a great piece of software and__not__ to the patch
itself. And I thing IMHO that the RPi can be great a great vector to enlarge
the user base of FreeBSD with all the benefits that this can bring to the
project.

------
mvanotti
My biggest problem with fbsd in the rpi is that it's really hard to cross-
compile ports for arm, and compiling everything in the rpi takes a lot of time
(I think it was half a day to compile tmux in the rpi A).

~~~
echochar
Can you run arm packages from a linux distrib under emulation?

[https://www.freebsd.org/doc/handbook/linuxemu.html](https://www.freebsd.org/doc/handbook/linuxemu.html)

~~~
toast0
Unlikely -- that's for i386 only (amd64 update is being worked on, IIRC)

------
bcook
I yearn for embedded *BSD routers.

~~~
anderiv
The Netgate RCC-DFF 2220 is available[1] right now, and performs very well as
a BSD router. It's not ARM, but it _is_ an embedded system/SBC. I use it with
pfSense, but it will run vanilla FreeBSD as well of course.

[1] [http://store.netgate.com/ADI/RCC-
DFF-2220.aspx](http://store.netgate.com/ADI/RCC-DFF-2220.aspx)

------
markhahn
to anyone who cares: why?

~~~
mwfunk
Obviously you think it's a waste of time- the burden is on you to explain why
not. Not why you don't work on it yourself, but why you think people who are
working on it shouldn't be.

~~~
something_23423
I think it's a completely fair thing to politely ask why people are spending
their time on this. Surely they have somg goal in mind.. Maybe they have some
bigger goal, like commercial OS's tuned to the RPi or something that only BSD
systems can do? Or maybe it's something simpler

~~~
mwfunk
Of course that's a fair thing to ask, but that post wasn't asking that
question. That post wasn't asking a question at all, it was clearly intended
as an insulting statement in the form of a question.

~~~
something_23423
I think there is an implied frustration with the fragmentation of "the open
source effort", which is ... understandable. It should have been written more
diplomatically. It seems to me to be a pervasive problem on anonymous forums.

