[179896] in North American Network Operators' Group
Re: Rasberry pi - high density
daemon@ATHENA.MIT.EDU (Rafael Possamai)
Mon May 11 18:09:07 2015
X-Original-To: nanog@nanog.org
In-Reply-To: <555121BF.4040708@mtcc.com>
From: Rafael Possamai <rafael@gav.ufsc.br>
Date: Mon, 11 May 2015 17:08:43 -0500
To: Michael Thomas <mike@mtcc.com>
Cc: "nanog@nanog.org" <nanog@nanog.org>
Errors-To: nanog-bounces@nanog.org
Interesting! Knowing a pi costs approximately $35, then you need
approximately $350 to get near an i5.. The smallest and cheapest desktop
you can get that would have similar power is the Intel NUC with an i5 that
goes for approximately $350. Power consumption of a NUC is about 5x that of
the raspberry pi, but the number of ethernet ports required is 10x less.
Usually in a datacenter you care much more about power than switch ports,
so in this case if the overhead of controlling 10x the number of nodes is
worth it, I'd still consider the raspberry pi. Did I miss anything? Just a
quick comparison.
On Mon, May 11, 2015 at 4:40 PM, Michael Thomas <mike@mtcc.com> wrote:
> As it turns out, I've been playing around benchmarking things lately usin=
g
> the tried and true
> UnixBench suite and here are a few numbers that might put this in some
> perspective:
>
> 1) My new Rapsberry pi (4 cores, arm): 406
> 2) My home i5-like thing (asus 4 cores, 16gb's from last year): 3857
> 3) AWS c4.xlarge (4 cores, ~8gb's): 3666
>
> So you'd need to, uh, wedge about 10 pi's to get one half way modern x86.
>
> Mike
>
>
> On 5/11/15 1:37 PM, Clay Fiske wrote:
>
>> On May 8, 2015, at 10:24 PM, charles@thefnf.org wrote:
>>>
>>> Pi dimensions:
>>>
>>> 3.37 l (5 front to back)
>>> 2.21 w (6 wide)
>>> 0.83 h
>>> 25 per U (rounding down for Ethernet cable space etc) =3D 825 pi
>>>
>>> Cable management and heat would probably kill this before it ever
>>> reached completion, but lol=E2=80=A6
>>>
>>
>> This feels like it should be a Friday thread. :)
>>
>> If you=E2=80=99re really going for density:
>>
>> - At 0.83 inches high you could go 2x per U (depends on your mounting
>> system and how much space it burns)
>> - I=E2=80=99d expect you could get at least 7 wide if not 8 with the rig=
ht
>> micro-USB power connector
>> - In most datacenter racks I=E2=80=99ve seen you could get at least 8 de=
ep even
>> with cable breathing room
>>
>> So somewhere between 7x8x2 =3D 112 and 8x8x2 =3D 128 per U. And if you g=
et
>> truly creative about how you stack them you could probably beat that
>> without too much effort.
>>
>> This doesn=E2=80=99t solve for cooling, but I think even at these number=
s you
>> could probably make it work with nice, tight cabling.
>>
>>
>> -c
>>
>>
>>
>
