If I wanted to build a power-efficient server..

[katit]

I read and re-read many topics and now need to decide. Basically, I'm trying to see what is going to be a most balanced solutions in terms of power, energy efficiency and initial cost.

I'm also thinking that I will use this new build for at least 5+ years, probably 10 or so. So, in my calculations I like to use $1/W/year just to make it easy. 20w vs 50w CPU will equal $30 per year in energy savings. And I want to calculate it over 3-5 years. Basically, if I can build system that's 60W more efficient - that will save roughly $180 which means I can put this money upfront.. So, thats my math. Now to constraints:

1. It's home NAS, will be used maybe 8-10hr per day. There will be no crazy jails. Maybe PLEX. Maybe. And it will not transcode more than 1 stream at a time. Look at CPU I have now (in my signature) - it's plenty..

2. I already have CASE, so the build is somewhat going to be around this case. It's SuperMicro 846 chassis with SAS2 backplane and 2x1200 GOLD PSU. I am aware (and I read this big topic about PSU and studd) about PSU efficiency, I may or may not go with smaller wattage platinum PSU. I will test how much fans using by pulling them, etc.

Main decision is between MB/CPU combos:

• Supermicro X10s (32GB of RAM max)

• The X10SL7-F ($240) is amazing if you are planning to go with more than 6-8 disks but don't want the cost jump with going beyond 32GB of RAM. It has a built-in LSI SAS 6Gbps controller which you can reflash to IT mode fairly easily which saves you from the mess of buying an M1015 and using it as an add-on card (not to mention the cost savings). On-board gives some small performance gains and this is a clear choice if you are looking for a good long-term system that is highly expandable. It has IPMI, dual Intel Gb LAN, lots of SATA and SAS and is a proven winner for many users in the forum. This is the current winner for those that are looking for that ultimately expandable server for home use.

• Intel Atoms (Avoton generation)
  • The new Intel Atoms kick butt. They use ECC RAM and can be loaded with 64GB of RAM if you buy special 16GB UDIMMs.
  • The Asrock C2750D4I ($250-300 but sometimes as high as $400) is pretty popular. The Marvell SATA ports have been known to be problematic for some people but the mainboard has built-in IPMI, 6 SATA ports on Intel SATA, dual Intel Gb LAN and has a single 8x PCIe 2.0 slot for expansion. This CPU has 8 cores (no hyperthreading) and seems to be very powerful despite its size. It is capable of doing transcoding of video streams with Plex and is the board found in the FreeNAS Mini. A review of what this board can do is available at Cyberjock's Blog. A 4-core version exists, the C2550D4I and is slightly less expensive for those looking to save a little money with a less powerful box.

Initially I was thinking X10 board. If I understand correctly this setup will cost me $250 + $60 for G32220 CPU. It has SAS on board. And it will give me huge convenience in cabling. I can hook up 1 cable to backplance to handle all the drives.

But then I read a little about Atoms. What is good about them? How much more efficient they are? Can I install this small board in my case? I know supermicro also makes those, why not listed and wny Asrock?
Cost seem to be $400 for board with CPU. But then I need another $100 for LSI card, correct? So, cost is like $190 over X10. Will it save this money over 3 years?

Basically, I want you to tell me how much better Atom-based system will be. I'm sure my useage totally permit's such board. I'm just not sure which way to go right now with a build.

 

[diedrichg]

I would look into the Haswell part G3420. It's a 54W 3.2GHz dual-core Pentium. It would be enough for what you are describing for your use case.

If you can wait until this fall, look at the Skylake parts that are going to come out, they should use even less power.

I'd suggest browsing the Intel Ark to filter the processors by socket and ECC compatibility.

 

[Ericloewe]

20w vs 50w CPU will equal $30 per year in energy savings.

No, it won't.

Higher TDP != Higher idle power consumption

 

[katit]

Agree. How do I know idle power consumption of different CPUs?

 

[cyberjock]

Agree. How do I know idle power consumption of different CPUs?

You'd have to read reviews on what their idle is. However, if you buy one haswell pentium against another haswell pentium (substitute any family of chip and line of chip), the difference in idle power is less than 5w and often less than 2w.

The TDP only tells you the maximum heatload you will have on the system. So if you can guy a Pentium X for $80 and the Pentium Y for 30 dollars more, and the $30 more sounds like a good deal because it's much faster in benchmarks, I'd spend the $30. It's nice to have a CPU that can clock up and power through the workload (even if its at a higher TDP) than to have a box that is slowly munching away at a lower TDP.

 

[Ericloewe]

You'd have to read reviews on what their idle is. However, if you buy one haswell pentium against another haswell pentium (substitute any family of chip and line of chip), the difference in idle power is less than 5w and often less than 2w.

The TDP only tells you the maximum heatload you will have on the system. So if you can guy a Pentium X for $80 and the Pentium Y for 30 dollars more, and the $30 more sounds like a good deal because it's much faster in benchmarks, I'd spend the $30. It's nice to have a CPU that can clock up and power through the workload (even if its at a higher TDP) than to have a box that is slowly munching away at a lower TDP.

I'd add that, within families, idle power is only a function of manufacturing variances (family being the same die).

The other day, a guy had an i3 somethingsomethingT and an unlocked Xeon (4C, no iGPU). System power was indistinguishable at idle.

It's something few reviews do, but comparing idle power within an architecture would be very interesting.

 

[NoTalent]

This is an interesting question, the reason being you have to define what 'idle' is in the first place.

For mobile systems like laptops and tablets, there is extensive testing done by ODM's before shipping optimizing battery life. This is only for the pre-installed software on the OEM drive. If you install other things then it will change the results.

For example, you purchase a HP commercial laptop--you are guaranteed that the system has been tuned to maximize battery life. Another example is if you buy a XYZ laptop and it has a bunch of apps that are always running in the background keeping the processor and other peripherals from going into their lowest power mode it will draw more power over time reducing its battery life. For most desktop systems, the ODM will run an EnergyStar and that's about it.

Now, saying all that--I have no idea what FreeBSD's power management features are. If it has an idle loop with a HLT instruction in it, then any modern x86 processor should be able to drop down to its lowest power mode and save a large amount of power. If there are constant interruptions (<50ms) then it might not be able to take advantage of the power savings features built in.

Another question is what your usage model is. If your system sits in a corner all day and serves up movies to you at night, then you will probably get lower power consumption than a user who has 5 clients connected to their NAS all day syncing files and using storage.

 

[katit]

Yes, my useage model is exactly like that. All day sits in a corner (in a basement actually). And then it may serve a movie at night. Or may not... CPU-wise I think it should idle most of the time. Because even movies - I'm going Kodi, so no transcoding. I am going to put disks to slip, also I read FreeNAS won't let them go to sleep for some reason? Mostly it's family library of pictures, movies (very rarely if at all watched). Documents for my wife's business (file share). I think disks will sleep about 50-70% of time.

If I use torrents - probably going to use single or 2 drives for it so there is no spinning "arrays" for junk data.

What is the thing about ATOM cpu's and boards? Seems like from all the responses I get people don't even consider those and suggest info for pentiums and X10 "by default"

 

[Darren Myers]

i really like the octocore atom's if i didnt have all the spare hardware thats in mine i would of went with a octocore atom to tinker with, and if it didnt work out then i'd get something more powerful like a full fledged xeon

 

[rogerh]

Only observations not experience: the Asrock Avoton board apparently has a constant extra 10 watts consumption for some purpose (possibly to connect the Marvell controller that doesn't work well anyway). The mini-ITX Supermicro Avoton board uses laptop memory (but I don't think it is that much more expensive or hard to get) and only has one PCIe slot. Personally I've got the 4 core Supermicro micro-ATX Avoton board which should fit your case and is not so miniaturised, with two PCIe slots, but I don't use it for FreeNAS. The only obvious disadvantages of the Avoton boards are cost (as you mention) and perceived lack of upgradability - but I don't know if anyone ever buys new CPUs for existing systems? And I think the single threaded power of the Avoton is rather below that of the basic Xeons you could get cheaper.

 

[Ericloewe]

The atom boards are nice, but expensive. @rogerh summed it up nicely.

What kills them for me is the limited connectivity. Xeon-D improves on that a lot.

 

[katit]

Nice is just s word :) how are they efficiency-wise comparing to x10 + pentium? They are more $$ but I can pay if difference will pay off in 3 years

 

[Ericloewe]

Not that much of a difference, especially on the ASRock boards (those have a permanent extra 10W consumption courtesy of the PCI-e switch).

 

[katit]

How much of the difference on SM board? Is it like 10-20 or 40-50w?

 

[Ericloewe]

How much of the difference on SM board? Is it like 10-20 or 40-50w?

ASRock C2750 vs Supermicro C2750? 10W, more or less.

 

[katit]

No, from my original post. X10 with pentium vs asrock atom

 

[Ericloewe]

I dunno. My X10SLM+-F with an i3 4330, 2x 8GB UDIMMs, two Noctua NF-F12 iPPC 3000 PWM fans @ 900RPM, two drive cages with 80mm fans at an unspecified speed, 6 WD Red 3TB (2.0 model) plus an 8-port GbE switch use 49-50W at idle, with the switch moving most of the network's packets around.

tl;dr - don't expect a huge difference. There's not that much to improve on.

 

[katit]

Ok, topic closed. Got G3470 + X10SL7-F
At least this combo should work for sure.