SOLVED Single or dual processors?

Daisuke

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Hi, I purchased a Dell 2100 FS12-TY with a single L5640 processor to replace my old NAS setup. My goal is to keep the power consumption to a minimal, since this will be a personal storage unit to backup my YouTube raw video library.

Should I purchase an additional processor? Link to server I purchased:
 
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blanchet

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For a backup unit, there is no reason to buy an additional processor.
It will increase your power consumption without any benefits in return.
 

joeinaz

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Unless you have a need to run virtualization, jails or Plex, You should be fine with just one processor. Do keep in mind removing one processor will also remove access to half of your DIMM slots so you will need to move your memory to support a uni-processor configuration.
 

Daisuke

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I see @joeinaz, from documentation, the system contains 18 memory sockets split into two sets of nine sockets with one set for each processor. I have 8 x 8GB installed, for a total of 64GB. I don't plan to use an SSD for cache, should I increase the memory for better performance or 64GB should suffice? I usually transfer very large files through network, saturating 2 x1Gbit cards.
 
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joeinaz

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I see @joeinaz, from documentation, the system contains 18 memory sockets split into two sets of nine sockets with one set for each processor. I have 8 x 8GB installed, for a total of 64GB. I don't plan to use an SSD for cache, should I increase the memory for better performance or 64GB should suffice? I usually transfer very large files through network, saturating 2 x1Gbit cards.
The memory you have is more than enough; Each processor socket is attached to a bank of 9 memory slots. You simply need to have all 8 memory DIMMs in the same bank that is attached to the specific CPU you are using when you have just one processor. In some cases there is a recommended order in which the DIMMs are populated and that can be found in the system documentation.
 

Jessep

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That CPU generation isn't known for low power.

Best bet for low power starts about E5 v2.
 

jgreco

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Best bet for low power starts about E5 v2.

v1 isn't bad. v2 was better though some of the higher end chips seem to have relatively high idle power; I have E5-2697v2 that idle at something like twice the idle power of an E5-2609 IIRC.
 

Daisuke

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v1 isn't bad. v2 was better though some of the higher end chips seem to have relatively high idle power; I have E5-2697v2 that idle at something like twice the idle power of an E5-2609 IIRC.
Should I ask the seller if they have a E5-2697v2 available to swap the L5640? Is it worth the effort? Thank you guys for your help.
 

Jessep

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Those are completely different generations, just don't be expecting super low power as the platform likely wont display it.
 

joeinaz

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Those are completely different generations, just don't be expecting super low power as the platform likely won't display it.

The keys to finding the sweet spot are the available hardware and the application. If the server is only being used for FreeNAS, the L5640 should provide plenty of processing power. It will cost about $11 a year to run (24/7/365). The nice thing about a dual socket setup is If in the future he wants to add additional compute and memory resources he can do so. The other nice thing about his system is the cost of the CPUs. An L5640 runs about $7 on eBay. It's even better he already has the hardware to house the CPUs.

On the other hand if he wants to run Plex and a number of VMs and or jails and he wants at least 12000 on the PassMark scale, a pair of X5680s will be huge in terms of power (up to 260w) or he can (after buying a new motherboard) run a single 2650 v2 and get the processing for about 40% the power cost.

Given what hardware he already has and what he is trying to do, I think he found that "sweet spot".
 

jgreco

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Thanks for the info, I was looking at the performance stats and L5640 was quoted better, I thought the power consumption will be better. Are we talking big numbers? I plan to make the disks sleep.

Any dual-socket platform is generally optimized for heavy-duty server tasks.

Dual socket platforms generally include more silicon on the mainboard, including a beefier PCH, and usually more I/O options.

Dual socket platforms generally use CPU's that are designed for heavier compute. The CPU's tend to be organized for more cores and larger cache.

Dual socket platforms generally have more RAM slots, and often seem to use hotter (== more watts) RAM.

And the modern platforms that deliver 12 drives in a 2U format have another gotcha: the fans. In order to get cooling air into the chassis to keep your drives alive, they use a high static pressure differential to suck air in through these tiny gaps around the 3.5" HDD's. This requires a lot of energy, which creates a lot of noise. Lots of hobbyists try replacing these fans, which can suck lots of watts, with consumer-grade crap like Noctua, in the hopes of "silencing" their beast, not realizing that the industrial grade fans are there to do a tough job and survive at least a decade of doing that tough job.

Once you commit to a prebuilt like the 2100, you're kinda stuck. One of the reasons I've promoted Supermicro heavily here in the forums is because you can pick an SC826 chassis but then plop a single socket board like an X9SCM or X10SRL in it, which will sip watts compared to the big iron, and is all you really need for a basic FreeNAS system.
 

Arwen

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@TECK, one comment. That particular CPU has 3 memory channels, (somewhat rare in the industry). You've installed memory in only 8 of the 9 slots. I'd suggest if you can find same / similar memory, populating that last 9th memory slot for your single CPU. That way you can get the 3-way memory interleaving on all 3 banks.

Of course, it's not critical.

Now days, Intel & AMD have CPU chips that support 4, 6 or 8 memory channels.

I remember the days when x86 CPUs used a FSB controller handled memory. AMD started putting the memory controller on their CPUs. Took Intel a while to adopt the better method. That did force new CPU sockets on us, (with new system boards). But, all around good decision.
 

Daisuke

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On the other hand if he wants to run Plex and a number of VMs and or jails and he wants at least 12000 on the PassMark scale, a pair of X5680s will be huge in terms of power (up to 260w) or he can (after buying a new motherboard) run a single 2650 v2 and get the processing for about 40% the power cost.
Your comment is very interesting, I was planning exactly this, adding in the future a second L5640 CPU and memory, in case I want to run Plex. Is the only additional software I would use, otherwise the setup will be purely for storage of raw video.
 

jgreco

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or he can (after buying a new motherboard)

I wasn't aware you could do that to a Dell 2100. Cite?

run a single 2650 v2 and get the processing for about 40% the power cost.

Why a 2650v2?

Why not an E5-1650v2 or an E5-2643v2?

Honestly after all these years I am still trying to figure out where people get the idea to put low clock parts in their NAS.
 

joeinaz

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"I wasn't aware you could do that to a Dell 2100. Cite?"
While I didn't specifically say to use the existing chassis, in replacing the motherboard, i should have noted the case may also need to be replaced.

"Why a 2650v2?"
In terms of number of cores, number of aggregate computes, power usage and price it is one of the most cost effective CPUs available (through eBay).

"Why not an E5-1650v2 or an E5-2643v2?"
1. Both the E5-1650v2 and the E5-2643v2 are more expensive on eBay.
2. Both the E5-1650v2 and the E5-2643v2 use more power (130w vs 95w)
3. The E5-2650 v2 offers more compute cores (better for virtualization applications)
4. The E5-1650 v2 does not offer the option to add a second CPU if the application needs grow beyond 1 CPU in the future.

Sample analysis: (using PassMark scores and eBay pricing)

L5640: Computes per dollar: 890
Dollars per core: $1.17
Computes per watt: 103.9

2650v2: Computes per dollar: 220
Dollars per core: $7.5
Computes per watt: 138.9

2643v2: Computes per dollar: 136.7
Dollars per core: $16.0
Computes per watt: 97.2

"Honestly after all these years I am still trying to figure out where people get the idea to put low clock parts in their NAS."


Years ago when the NAS boxes generally did just the "NAS" function, there was not the focus on the CPU. Some FreeNAS systems are even build around the "Atom" series of Intel processors. The advent of Plex as an application and virtualization completely changed the game. Today it's not unreasonable to build a "superserver" simultaneously supporting FreeNAS, Plex and a few VM or jails. My last FreeNAS system ran dual E5640 cpus and supported a 12 disk FreeNAS installation Plex and three VMs under VMware. My current system will uses a single E5-2650 v2 and gives me more computes, the same number of cores and uses about 1/2 the wattage.

The intended application and potential growth should drive the chosen hardware...
 

Daisuke

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@joeinaz and the rest of great helpers, I contacted the seller and he is offering me an upgrade package including the second L5640, heatsink and 10x8Gb memory sticks for $110 shipped to my door, to fill all memory banks. I ordered the package.

I plan to install Plex and also a jail where I will run dnsmaq for my local DNS resolving. Honestly, I believe dual L5640s are more than sufficient for my planned usage. Your thoughts? I mean, I can always upgrade the CPUs later, with everything in place. I just feel having a more recent/expensive CPU model will not be beneficial and the power consumption will be minimal with my actual usage.
 
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Donny Davis

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In my experience faster cores have always topped everything else for my use cases.
 
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