[K12OSN] Life after LTSP

[Robert Arkiletian]

On Tue, Nov 9, 2010 at 8:25 AM, Jeff Siddall <news at siddall.name> wrote:
> On 11/08/2010 10:07 PM, Robert Arkiletian wrote:
>> On Mon, Nov 8, 2010 at 12:59 PM, Jeff Siddall <news at siddall.name> wrote:
>>> On 11/08/2010 03:27 PM, Robert Arkiletian wrote:
>>>> In my opinion,  the days of LTSP are numbered. For a few different reasons.
>>>
>>> Yes and no.  See my comments inline.
>>>
>>>> 1)
>>>> hardware is so cheap now. You can buy a brand new power efficient and
>>>> fast  desktop system for about $200 (not including monitor).  Thin
>>>> clients are actually *more* expensive now.
>>>
>>> Yes, hardware is petty cheap but even the most power efficient desktop
>>> systems are about 5 X the power of a typical thin client.  Over the life
>>> of the client that can exceed the hardware cost.  Plus any fanless
>>> system is still a slow systems, and LTSP can make those slow fanless
>>> clients feel like fast noisy desktops.
>>
>> I am going to measure my clients power usage tomorrow. I have Dell
>> Opitiplex dual core Celeron e1400 (2Ghz) cpu with Intel Q43 chipset.
>> and 2GB ram. Wondering if anyone has measured the power usage of a
>> true thin client (eg. Atom) system.
>
> Yes, definitely.  I measure the power consumption of all my systems.
>
> My typical Atom based clients are D945GSEJTs and they run about 14 W at
> the plug.  The board itself is spec'd somewhere in the 12 W range.
>
> A very low power desktop system with a 45 W TDP single core Sempron
> LE-1200, M2N PV-VM board and 80 GB Seagate ATA HD still runs at 57 W
> idle, 86 W at 100% CPU.  The hard drive runs about 9 W so you can remove
> that much for a diskless system.
>
> By comparison, a relatively modern Phenom II X4 940, with dual Seagate
> 250 GB SATA runs at 71 W idle and 171 W with the CPU running 100%


Got some numbers from my kill-a-watt meter:

Dell Optiplex 760 (running DRBL client)
e1400 dual core Celeron (Allendale 65nm) 2.0Ghz
Q43 Intel chipset
2 GB ram

gnome desktop + FF(google.ca)  = 45W
gnome desktop + FF(youtube 720p fullscreen) = 60-65W (fluctuates)

A real dual core Atom thin client running LTSP ~ 19W
(I don't have an Atom based thin client to test. This is from some
googling ymmv)

Assume average usage is 49W for the Dell over a work day.

49-19= 30W difference (omitting monitor)

30W * 8hrs/day * 190 work days/school year = 45.6 KWh for 1 system/year

Assume a large school has 180 systems.

180 systems * 45.6 KWh/system/year  = 8208 KWh/year for 1 school

At $0.08/KWh for electricity for public sector K-12 schools (this
varies where you live)
(see http://www.eia.doe.gov/electricity/epm/table5_6_a.html)

8208 KWh/year * $0.08/KWh = $656.64 / year/ school   savings using fat
diskless vs thin client

Oh course this will vary depending on your own systems but it gives a
ball park. If a district has say 15 schools of this size that's almost
$10,000 savings per year for a district. But that's assuming you have
100% homogeneous systems (rarely the case).

If I have made any errors or omissions please correct me.


-- 
Robert Arkiletian
Eric Hamber Secondary, Vancouver, Canada