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dsdreamer
2008-04-24, 14:32
I have been enjoying my pair of SB3s for quite some time without thinking about the energy costs (financial and environmental) of running an old PC 24/7/365 to act as a dedicated server. Now I want to do something about it, and wondered what options people have employed successfully.

Some ideas of my own, that I have implemented or tried to:
1) Underclock the PC CPU and Memory in the BIOS
2) Remove unwanted hardware such as graphics accelerators (since the machine is running headless)
3) Auto standby after some hours of inactivity

I would really like to combine #3 with Wakeup on LAN, but I couldn't get that to work (yet). Does the the firmware that comes with SC 7.0 still support the WOL magic packet?

Do other people have different ideas that they could share here? It may help a few people and save a few mega Joules of energy aggregated over the SD community :-)

--Dsdreamer

CatBus
2008-04-24, 15:16
Here's my thoughts based on my experience along similar lines:

CPU and memory underclocking won't get you anything but headaches. Auto-standby seems like a very good idea if you can get WOL working. Removing unneeded hardware certainly can't hurt, but it's probably more effective to buy/replace hardware that's more suited to power-saving. Examples: laptop hard drives use MUCH less power than their 3.5" counterparts--they're also quieter. You can get an adapter that lets your put a 2.5" disk into a 3.5" enclosure with appropriate connectors. Sure they're slower (part of the power savings comes from fewer RPMs) but I only notice that when copying music to or from the server. I'm considering SSD when the price becomes realistic. Low-wattage efficient power supplies are better than high-wattage once that crank out heat. I would imagine fanless power supplies tend to be much more efficient because they have to be. Lastly, some CPUs are better than others. A Pentium 3 or Core-series CPU is fairly efficient, but there's no saving a P4. Not sure about the AMD side. Hope that helps.

pfarrell
2008-04-24, 15:31
CatBus wrote:
> others. A Pentium 3 or Core-series CPU is fairly efficient, but
> there's no saving a P4. Not sure about the AMD side. Hope that helps.

Look at VIA and others if you want serious energy savings. Anything
Pentium is really a space heater.

SqueezeCenter doesn't need much CPU power, there are many postings in
the forums about fanless VIA chip servers.

SuperQ
2008-04-24, 16:29
The best way to save electricity is to just use SqueezeNetwork. ;)

WoL has been supported since 6.0 afaik (SqueezeBox 2). If you could give us more details about your server, we could probably give you more specific tips.

Have you upgraded to an 80Plus PSU? Have you put your server on a watt-meter? (WattsUp or kill-a-watt are good ones)

dsdreamer
2008-04-24, 17:58
Here's my thoughts based on my experience along similar lines:

CPU and memory underclocking won't get you anything but headaches.

I'm not sure why that should be? Power consumption is proportional to clock frequency all else being equal, and if a synchronous digital circuit has timing closure under normal clock speeds, it sure will when its run slower. Is there a particular technical issue I might be expected to hit?

http://en.wikipedia.org/wiki/Underclocking

Anyway, my experience in using 3/4 of the rated clock speeds was noticeably less heat and less noise (due to the temperature controlled fan running slower) and I see no down-side as yet.

I do like your suggestions, e.g. using laptop drives. As regards processors, I am using an old AMD Athlon, so lots of room for improvement there --- but it will take an entirely new hardware solution to make that practical.

Thanks for your post,

--dsdreamer.

pfarrell
2008-04-24, 18:16
dsdreamer wrote:
> Anyway, my experience in using 3/4 of the rated clock speeds was
> noticeably less heat and less noise (due to the temperature controlled
> fan running slower) and I see no down-side as yet.

I've also had good stability with underclocking.
It generally reduces CPU power directly by the percentage underclock, so
a 3/4 underclock will save 75% of the CPU's power.

Not clear how important that is, the CPU a big user of power but there
are many others. The power supply typically wastes a huge amount, and
fast disk drives are power sinks.


--
Pat Farrell
http://www.pfarrell.com/

dsdreamer
2008-04-24, 18:21
The best way to save electricity is to just use SqueezeNetwork. ;)


But I only like to listen to lossless FLAC files :-)



WoL has been supported since 6.0 afaik (SqueezeBox 2). If you could give us more details about your server, we could probably give you more specific tips.

Based on your comments I dug deeper into my BIOS settings and found the switch that had eluded me before.


Have you upgraded to an 80Plus PSU? Have you put your server on a watt-meter? (WattsUp or kill-a-watt are good ones)

I am using a Shuttle SFF PC, and there are no 80+ PSUs for these boxes AFAIK. I was looking at purchasing a kill-a-watt meter, though.

So for now, my low investment solution is to use a short time-out before suspend to S3 and using the SB3 to send a WoL packet to wake up the server only when needed. In the longer term, I would like to build a custom box with low power in mind, using VIA or possibly the Intel Atom if I can find a suitable MOBO when the time comes.

Thanks for your comments,

--dsdreamer

Honva
2008-04-24, 19:00
I have been enjoying my pair of SB3s for quite some time without thinking about the energy costs (financial and environmental) of running an old PC 24/7/365 to act as a dedicated server. Now I want to do something about it, and wondered what options people have employed successfully.

Some ideas of my own, that I have implemented or tried to:
1) Underclock the PC CPU and Memory in the BIOS
2) Remove unwanted hardware such as graphics accelerators (since the machine is running headless)
3) Auto standby after some hours of inactivity

I would really like to combine #3 with Wakeup on LAN, but I couldn't get that to work (yet). Does the the firmware that comes with SC 7.0 still support the WOL magic packet?

Do other people have different ideas that they could share here? It may help a few people and save a few mega Joules of energy aggregated over the SD community :-)

--Dsdreamer

On newer CPUs, underclock may not give you saving because the CPU will underclock itself during idle anyway. Undervolt will save you a lot more. How much power saving depends on how old your CPU is. Older CPUs without "speed step" or "cool & quiet" will burn you a lot more energy. My old Athlon XP 3000 burns 102W during idle. My Athlon x2 3600 only burns 45W when idle and 39W after undervolting.

WOL will save you the most energy and is easy to do. Most computers only use 1-5W during S3 sleep and wake up time is typically 20s (of which 15s was waiting for hard drive to spin up).

If you are really concerned about power saving but want to maintain performance, forget about desktop boxes. Get a cheap old notebook with something like a Pentium M. While I spent hours trimmed and tuned my desktop server down to the impressive 39W, my Gateway notebook used only 12W after 5min of tweaking.

If you want to put together a new SFF box, wait for the upcoming (May) Intel Atom CPU and Centrino 2 chipset. Expectation are that they are really good on performanc/power ratio.

funkstar
2008-04-25, 03:46
I've voiced my thoughts on this before, here is a link to the post: http://forums.slimdevices.com/showthread.php?p=288939#post288939

In short, it takes a lot more to be 'green' than just using less electricity :)

peter
2008-04-25, 03:59
funkstar wrote:
> I've voiced my thoughts on this before, here is a link to the post:
> http://forums.slimdevices.com/showthread.php?p=288939#post288939
>
> In short, it takes a lot more to be 'green' than just using less
> electricity :)
>

My thoughts: There's only a limited amount of power.
If I don't use it someone else will.

Regards,
Peter

bobkoure
2008-04-25, 08:07
I know I'm being contrary to "accepted wisdom" somewhat here, but if you've got a fairly large collection, laptop drives don't offer power savings. Yes, they're low wattage, but they're also low capacity.
For instance, WD has a "green" 1TB drive that uses around 5W.
How many laptop drives would it take to have that much capacity, and how many watts does each one use?

forddonald
2008-04-25, 09:18
One alternative approach is to consider virtualization. The equation then becomes: if you were willing to run a PC full time to support the music serving requirement, and you have another PC for some other regular, recurring workload, then virtualizing them and placing the both of them (or more, as the case my be) on a single system means you're actually paying half to power each.

While virtualization doesn't save power directly, it does let you aggregate workloads that traditionally would have been done by multiple PCs on to one, thereby allowing the power down of the second PC, third PC and so on, which does relate to power/cost/Earth savings.

There are a few VMs pre-built for SqueezeCenter serving available today.

http://www.vmware.com/appliances/directory/1207

http://www.vmware.com/appliances/directory/1208

bobkoure
2008-04-25, 09:50
Right - but if you're going to run a box 24x7, you can just run squeezecenter right on there.
Don't get me wrong, VMs are great, but a lot of the attraction for server VMs is that you have a better shot at server stability if you don't have to worry about the interplay between server apps. VMs also have the advantage that you can have different sets of users/permissions, and the two are as isolated as separate machines would be (actually an interesting thing for a home user - run a separate "PC" in your DMZ without having to be overly paranoid about outside attacks).
So anyway, yeah, reducing two (or more) servers to one definitely saves power - but there is some overhead, particularly if you're running a VM on top of another OS rather than having a simple extra-efficient "server" to run VMs in (which is pretty pricey) and if you're going for low power and aren't worried about server-app interaction...

syburgh
2008-04-25, 13:27
Agree with most of the previous posters-- I use a Core based system with passive cooling and laptop drives. It's about 19W with SpeedStep at lowest speed (never increases except when transcoding FLAC to MP3 files). I use WOL with a 30 min timeout to suspend the system and wake using SB3 (takes a few seconds to resume). Understand the Controller will soon have this functionality.

Economics will support running SqueezeCenter in a VPS at some point soon-- each FLAC stream is about 1 Mbit/s and latency is not bad with fast connections (e.g. some cable services, FIOS, etc.). The bandwidth costs could be an issue (about 450 MB/hour), but I don't spend enough time at home for it to be an issue (maybe play music 20-30 hours/month). Currently storage is probably the most significant limit-- most VPS plans have small limits (tens of GB) as they have to absorb cost of users who make larger IO demands (e.g. DB, mail spool, etc.) than a single user SqueezeCenter. Something like a cheap Xen VM (e.g. Slicehost) for $20/month would probably be good if it had the necessary storage...

Not a great idea to run SC7 open to the public Internet, but many home routers support VPN...

bobkoure
2008-04-26, 07:06
Not a great idea to run SC7 open to the public Internet, but many home routers support VPN...
Or you create a virtual machine, give it read-only access to the "base" OS that actually contains all your music files (the same way you'd do if it was two machines networked together). Run SC on that virtual machine, and expose that VM to the 'net.

Even if someone breaks in, there's not much they can do, and you can repair any damage by stopping the VM, copying one file (backing up an entire VM is just a matter of copying a file or two), and restarting (you might want to disconnect the machine from the 'net until you've picked a different password).

All theoretical for me as I have a commercial router and ipsec connections to my workplaces.
I do use VMs on a regular basis, though. The easiest way to get a free one is to
1) download "player" from vmware
2) download a pre-built OS, like maybe grandma-lamp (http://www.vmware.com/appliances/directory/581)

I do work for customers who sometimes have ....idiosyncratic server setups. Once I've duplicated the idiosyncrasy in a VM, I can do most of the work at home, which I much prefer to sitting in a (usually loud, usually uncomfortably cold) server room somewhere.

I've also persuaded one of these places that's currently got all their employee machines *really* locked down (people were opening their own private email, which was fine, and then clicking on all attachments, which sucked for the IT guys; ditto for downloading and installing EXEs) to put VMs on all these machines, where the employee gets to be a windows admin in that VM. If the user has problems, or if the VM shows up in Snort (so probably infected), it's a two-minute operation for IT to simply bring that VM back to baseline.
The IT guys are pretty happy, and the users see this as being lots better than not being able to do anything at all

Zaragon
2008-04-26, 09:36
One interesting point about using Squeezeboxes in a green fashion that always seems to crop up is the comment along the lines of " I'm going to build a low power server ".

So I was wondering in global enery and resource terms is going out and buying new components, which used electricity in manufacture, fuel in distribution, resources in construction balanced by the lower energy consumption actually less than running an old PC at higher electricity usage but no landfill or need to recycle the components with their associated enery and fuel needs.

In short which is greener use the older more power intensive PC or junk it and use a new system. Of course you use less electricity which reduces your bill which may be all some people care about.

Not withstanding that all the other ideas like standby are good one.

dsdreamer
2008-04-26, 14:28
One interesting point about using Squeezeboxes in a green fashion that always seems to crop up is the comment along the lines of " I'm going to build a low power server ".

So I was wondering in global enery and resource terms is going out and buying new components, which used electricity in manufacture, fuel in distribution, resources in construction balanced by the lower energy consumption actually less than running an old PC at higher electricity usage but no landfill or need to recycle the components with their associated enery and fuel needs.

In short which is greener use the older more power intensive PC or junk it and use a new system. Of course you use less electricity which reduces your bill which may be all some people care about.

Not withstanding that all the other ideas like standby are good one.

Under-clocking my old AMD Athlon XP processor, removing redundant hardware and having the machine in S3 state at least 90% of time collectively result in more than an order of magnitude improvement without requiring any new hardware to be manufactured or transported.

Although having a specifically engineered solution for low energy would be fun to do and give a certain amount of satisfaction, I should probably reserve that option for when I have an actual hardware failure to contend with.

Thanks for sharing your thoughts.

--Dsdreamer

Philip Meyer
2008-04-27, 05:02
Does anyone know what the power usage is in "power off" state for each SB model? I tend to leave my SB3 and Transporter permanently plugged in.

What is the best plugin to install to enable a command to be sent to put the local server to sleep/hibernate? I'd like to do it as a manual action (select a menu option on the SB), or when using the Sleep button.

Phil