Jan Stary <hans@stare.cz> wrote:

quoted text
> last night, I installed 4.1 on the new ALIX.1C:
> http://www.pcengines.ch/alix1c.htm (see dmesg at bottom).
> The intended use of the box is a home router/firewall/NAT/DNS/DHCP
> for my home "network" of about four computers (heterogeneous).

I recently got a Soekris net5501, which is uncannily similar (I
guess they're both based on the same reference design), and moved
the same kind of infrastructure functions to that box, so I had to
look at similar decisions.

quoted text
> Firstly, swap (i don't really mind reinstalling).
> 
> The machine has 256M of RAM, and the storage is a 2G CF card (seen as
> wd0). The machine is mostly idle (basically just routes). How much swap
> do you think I should set for such operation? For regular operation,
> I don't think I need a swap partition at all

Indeed.  Just run without swap.

quoted text
> (how would I do that?  A 'b' partition of zero size, as it has to exist?),

Actually, it does not have to exist.

quoted text
> but to be able to save possible core dumps, I am thinking of 300M
> swap and 300M /var (to hold /var/crash). Is this reasonable?

Do you want to do kernel development and debugging on that box?

It depends on how you view the machine.  I decided to forgo the
usual multiuser system approach and treat the box as an appliance.
The whole point is that it will just sit there, performs its job,
and I won't have to touch it.  I didn't twiddle with settings unless
required for functionality.  No need for a pretty shell prompt.  I
didn't even bother to create a user account.  What for?  I'd have
to prefix nearly all commands with sudo anyway.  Partitions?  There's
only a single partition 'a'.

quoted text
> Secondly, the network interfaces. The box comes with an on-board
> vr0 at pci0 dev 13 function 0 "VIA VT6105M RhineIII" rev 0x96: irq 10
> which I currently use as the external iface, and the PIC slot holds
> rl0 at pci0 dev 12 function 0 "Realtek 8139" rev 0x10: irq 11
> which is used as the internal iface. I also have the following
> cards in my hands, and I would like to figure out which combination
> of external/internal would give me the "best" performance (if it
> makes any difference at all):
> 
> 	Intel PRO/100 S Desktop adapter
> 	3C905C-TX-M Etherlink 10/100 PCI 3

Well, near the top of /sys/dev/ic/rtl81x9.c you can find Bill Paul's
famous rant on just how crappy the rl(4) hardware is.  He concludes:
"It's impossible given this rotten design to really achieve decent
performance at 100Mbps, unless you happen to have a 400MHz PII or
some equally overmuscled CPU to drive it."

That was written quite a few years ago, and as wimpy as a Geode
LX800 may seem today, it qualifies as an "overmuscled CPU".  Any
of your cards above will be fine.  I doubt you're going to notice
any difference.

quoted text
> I don't have any idea about what amount of e.g. fragment reassembly the
> external/internal iface needs to do, and which card (or which card's
> driver) is "best" for that.

Fragment reassembly doesn't happen in the driver.

quoted text
> Thirdly, the CF storage. Having read
> http://www.kaschwig.net/projects/openbsd/wrap/#mfs
> http://blog.innerewut.de/2005/05/14/openbsd-3-7-on-wrap
> http://blog.innerewut.de/2005/05/19/openbsd-3-7-on-wrap-revised
> http://blog.innerewut.de/2005/06/03/small-update-on-openbsd-3-7-on-wrap
> (which apply to 3.7 on WRAP, the predecesor of ALIX), I am concerned
> about the CF wearing off.

I'm not.

quoted text
> As these articles are from 2005 - do these things still apply to
> newer CF cards, and should I therefore set up a mfs?

I don't think these things still applied back then either.  At
EuroBSDCon 2005, Poul-Henning Kamp, who has a lot of experience
with this, broached the topic in one of his talks and basically
said that it wasn't a concern in practice and that he wanted to try
out a flash drive as his laptop disk.

quoted text
> What else should I do to make the CF card live longer (noatime
> comes to mind of course).

Buy a bigger flash so wear-leveling can spread the writes around.
But with CFs now starting at 1 GB, this isn't an issue either.

-- 
Christian "naddy" Weisgerber                          naddy@mips.inka.de