Why are standalone NAS units so slow?

[Judgeless]

I have been running a dedicated PC with an Intel Q9550, non RAID 7200 RPM Hard drive and Windows 7 as my file server. The box uses a lot of power and I would like to replace it with a off the self NAS unit.

When I look at the comparison charts the fastest unit is 108MB/s reads. None of them will saturate 1Gb Ethernet. That does not make sense to me. Here are some of my benchmarks using two Windows 7 boxes.

File copy 121MB/s (968Mb/s)

1Gb/s Ethernet transfering at 933Mb/s (117MB/s) 98% utilization

Are there low cost NAS units that will do this?

 

[stevech]

Look at the performance numbers on this website's NAS section. My reading of these and numbers from newer NASes from leaders Synology and QNAP show that at the $200 and up level, these will achieve 70MBytes/sec with large files - like videos or other Mega/Gigabyte sized files. Of course, any transfer is much slower with a smaller files.

I've also read that many/most of the heavily retail marketed NASes have poor performance as compared to the above, such as Seagate, Netgear, IOmega, at this price point.

To get to 75% of the capacity of gigE, it takes a large file due to rotational latency (or a solid state disk), AND an efficient TCP stack, and a good implementation of CIFS/SMB. And a decent CPU speed, like the dual core 1.6GHz ones in these NASes.

 

[Judgeless]

Stevech thanks for the feedback. The $200 price point sounds great. Going from 120MB/s down to 70MB/s does not sound good. I understand that it takes a robust system to handle 75% or 98% utilization of 1G Ethernet. It should be a goal of companies that make NAS units.

I did look at the performance numbers. The fastest NAS unit listed is 108Mb/s. I can get 120MB/s using a Windows 7 box without RAID. The machine consumes 300 watts. My goal is something in the 10 watt area. I am sure in a couple of years this will be popular. I am curios if there is anything close today.

 

[teknojnky]

most consumer nas do not have anything close to a Q9550 cpu, and usually 1 gig or less ram.

vs your desktop Q9550, I am assuming it has at least 4 gig, if not more. And being non-raid does not have to consume cpu resources generating parity data.

also non-raid vs raid is different as well, parity calculations have to be made (and written to disk) for raid which, depends heavily on CPU (or a hardware raid controller if so equiped).

the readynas pro 6 and rack mount devices can more than saturate a gbit link, they have much more powerful cpus than most of the nas's available.

Another over looked reason is the disks, using low power/desktop disks, vs raid ready enterprise disks can have a measurable effect on performance as well.

The client also has a large part in the performance exhibited, jumbo frames, good cables/network components, etc.

I'm sure several of the other more expensive models of the brands can also easily saturate gbit links with appropriate disks and network clients.

My readynas pro business (original v1) has reached over 180MB/s via gbit bonded lacp links and multiple clients writing to disk.

 

[Judgeless]

I understand that a Q9550 is over kill. In the benchmark it is saturating 1Gb Ethernet with 20% CPU utilization. http://mbu.com/232.jpg I am not interested in bonding two Ethernet ports for more speed. I want a NAS box that is cheap, low power and can saturate a single Ethernet port.

 

[teknojnky]

I want a NAS box that is cheap, low power and can saturate a single Ethernet port.

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

good luck.

Your best bet is to roll your own, there are several threads here and plenty more on google on how to build your own nas.

Only then will you come close to meeting your objectives, because only you can determine what tradeoffs you will be willing to have to make.

 

[Judgeless]

I understand the trade offs of power vs performance vs cost. I am just shocked that saturating 1Gb Ethernet is not the number one goal of a company making a low cost NAS box. 1Gb Ethernet is the weakest link. Most new 7200 RPM hard drives are a lot faster than 1Gb Ethernet.

It would be great if a company used a quad core ARM processor that would consume very little power. Using a Q9550 is bad because the CPU alone is over 80 watts.

 

[teknojnky]

There are lots of models with single/dual core atom powere cpus (with hyperthreading, that means 2 or 4 virtual cpus), which I would expect to equal or outperform even the most newest quad arm cpus.

But I would not expect either to consistently saturate gbit.

Even if the ARM have more raw horsepower than an atom, I would expect the atom device to put up a good fight due to the maturity and optimizations inherent in x86 linux vs ARM.

Not only that, I would suggest that x86 has the much larger headstart with supporting various add-ons etc which have not been ported to arm.

see also @ http://www.anandtech.com/show/5071/netgears-marvell-based-readynas-nv-v2-review

Of course, one day we may well have nas that are powered by cellphones and that you can easily carry around with 2.5" or smaller 10tb SSD drives, with 10gbit nics.

 

[Judgeless]

ARM is making a lot of headway. The latest Atoms still are over 10 watts with the chip set. For the same performance on ARM you are looking at .25 to .5 watts.

I have a 64GB SDXC card in my Dell Streak phone now. Many of the new LTE phones can get 40Mb/s out of the air. Technology is moving fast.

These are standby numbers but ARM is a lot lower power then Atom. http://mbu.com/266.jpg

 

[Judgeless]

see also @ http://www.anandtech.com/show/5071/netgears-marvell-based-readynas-nv-v2-review

It does pretty good on the benchmarks.

http://www.smallnetbuilder.com/nas/...harts-netgear-readynas-pro-2?showall=&start=1

I wonder how much power it uses.

It would great if they could show power consumptions in the benchmarks. Even if they just used a kilowatt wall adapter.

 

[teknojnky]

from the anandtech review;

ReadyNAS NV+ v2 Power Consumption
Power Off 0.9 W
2 x 1TB RAID-1 Volume with High Network Load 24 W
3 x 1TB RAID-5 Volume with High Network Traffic 28.3 W
4 x 1TB RAID-5 Volume with High Network Traffic 34 W
4 x 1TB RAID-5 Volume Rebuild 36.8 W
Idle (4 x 1TB RAID-5) 12.3 W

Keep in mind though, that netgear has positioned these as 'consumer' vs 'pro-sumer' devices, and thus a much more basic feature set (ie only cifs, no iscsi, etc).

It sucks, but as I said earlier, you are likely to be better served to roll your own, if you are wanting the the lowest power/cost and highest performance/features, because device manufacturers are wise to selling the stripped down/low performance models and ramping up the cost to get the performance/efficiency/features you really want.

 

[stevech]

I bought an admittedly early Netgear NAS. It was beyond junk and square into the area of C-RAP.

Unforgivable, per me, that they had the nerve to sell that.

 

[thiggins]

It would great if they could show power consumptions in the benchmarks. Even if they just used a kilowatt wall adapter.

Power consumption is noted in product reviews and in the NAS Finder data.

You are not going to find what you are looking for, at least not now. Need an Atom-powered or better NAS to saturate a Gigabit link. That goal is only going to be reached for large file transfers. Once you start transferring
smaller files, overhead and drive head seeks severely reduce speed. Look at the NASPT benchmarks and the difference between file and folder transfer.

 

[Judgeless]

Thanks for the link. Most of what I do involves large files from one machine to another. I know this is not 100% true but if it can saturate 1Gb Ethernet with large files, it should do well with small files.

This is a great web site and forum. I will keep checking back for a solution.

 

[teknojnky]

fyi, was bored so here's some fresh screens

copying 48g bluray iso from pc (SSD) to readynas pro business (v1) saturates gbit/

edit: btw, this is also dual redundancy (ie raid-6)

6x SAMSUNG HD204UI [1863 GB]

http://www.amazon.com/gp/product/B001ENER2O/?tag=snbforums-20

My ultra4 (single core atom w/ hyperthreading) with same copy peaks about 75mbs, but the ultra4 has been thru a couple expansions and has mixed drives which probably isn't helping its performance, as I recall some earlier tests when I first got it peaking 90ish mbs.

Ch 1 : Seagate ST4000DX000-1C5160 [3726 GB]
Ch 2 : Seagate ST31500341AS [1397 GB]
Ch 3 : Seagate ST31500341AS [1397 GB]
Ch 4 : Seagate ST4000DX000-1C5160 [3726 GB]

 

[Judgeless]

Those numbers are really close to mine http://mbu.com/232.jpg

The NETGEAR ReadyNAS Duo 2-Bay (Diskless) is $208 on Amazon. http://tinyurl.com/6vsnnw5 and the review shows it consumes 32 W power draw with the drives spun up and 17 W with them spun down. I would guess typical operating power would be in the mid 20 W area. I wonder why your bench marks are higher than the person that reviewed that drive.

If I designed a consumer based NAS unit my number one goal would be to saturate 1Gb Ethernet.

 

[teknojnky]

that is the first generation duo, that has like 400 MHZ, not GHZ, sparc based cpu. Yes, less cpu than a modern cell phone.

The same cpu that the first generation nv/nv+ uses.

Both these devices get about 20-30mbs.

The recently released SECOND generation duo/nv+ use ARM base cpu and is what is linked previously to anandtech's review.

These are still low power, low cost, low performance, low feature devices.

The ultra, ultra+, and pro series use x86 cpus, from single core or dual core atoms, to actual dual core pentiums in the ultra+ 6 and pro 6.

Netgear has purposefully segregated performance levels (and some features) into the more expensive models.

While personally I think there are too many models, and I really dislike the fact that they have purposefully removed features from the cheaper devices, that is their way to make money.

Of course as an end user, one of the highest priorities is performance, no one wants slow storage. However, performance is not free. You have to pay the piper somehow.

IE dedicated windows PC storage, high performance, high cost, high power usage. Or an x86 linux based appliance with sufficient cpu/memory, either way neither is cheap, nor likely will be cheap any time in the near future.

As I've repeatedly said, you can get gbit saturated peformance, but you are going to pay for it. Or you can take various amounts less gbit saturation and save money (and energy).

specific x86 cpus used in the readynas models

 

[jerryk]

If I designed a consumer based NAS unit my number one goal would be to saturate 1Gb Ethernet.

I would expect a NAS to have good performance, but not at the cost of features such as expandability, ease of upgrading to larger disks (no rebuilding arrays from backups), reliability, easy of management, media support, multiple client device type (Mac, iPad, Android, Unix, Windows, etc) support.

I get all of this and great performance from my ReadyNas Pro. It also does pretty good with power when it is idle (99% of the time).