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Base Station (n) writing slow to the a HD???

The Stig said:
You see, I have plugged both HDs into my MB with a USB cable and I get a transfer rates 16.4 MB/s for the Lacie and 17.2 MB/s for the I/O magic. How are you going to tell me that it won't work correctly because my HDs have a MAC transfer rate? I know what that is, it is 16.4 and 17.2 MB/s. Since they are over a wireless connection I would guess the rates would be a bit lower. Somewhere between 10 MB/s and 15 MB/s. But anything slower than that is just stupid. Why would I guy drive to only get the read/write speed of G device. A G-router with a USB slot could do pretty much the same thing. N should be better and it is not. They do guarantee that the router is up to 5 times as fast and it is not. Apple agree with me and have escalated my problem to their hardware people to look into it. I don't see where you are coming from?

The Stig
Click to expand...

I am saying you reached the limited of the hard drive transfer rate, not the network.

http://www.westerndigital.com/en/products/Products.asp?DriveID=233&Language=en

Transfer Rates
Buffer To Host (Serial ATA) 3.0 Gb/s (Max)
Buffer To Disk 61 MB/s (Sustained)
Click to expand...


This is what I am talking about. Add over head of ethernet then overhead of 802.11n then the sata or ide protocol. In theory, the limit of both 802.11g and n could be the same transfer rate due the limit of the processor on the controller on the lacie box NOT THE NETWORK.

I did not just make this up, it isn't the network. I bet you engineering will find the bottle not is between the that HD controller and hard drive itself and it hits the write limit of the hard drive.

this is reason why RAID and SAN technology came out to overcome this bottleneck and have hard sustained read and write rates to hard disk.

That setup isn't design to sustain high transfer rates.
 
Rob from Apple support called me back yesterday to try somethings. He got me to plug straight into the base station and change some of my Ethernet setting to see if things sped up at all. He had me change my MTU setting to 1492. He had me run too tests, 1 test with the speed settings on "auto select" and the other test with the speed setting "100baseTX" with the Duplex set to "Full-duplex, flow-control". After I ran those tests he wanted me to e-mail him with the results. Here is what I sent him:


Hey Rob,

With the speed set to auto select it starts off around 5.5 MB/s (still isn't that good) but then drops to 1.0 MB/s and ends with a write average of 2.1 MB/s. Read speed is an average of 6.3 MB/s.

With the speed set to 100baseTX with Duplex set to full-duplex, flow-control is starts off around 5.7 MB/s again but then drops to 0.7 MB/s and ends with a write average of 2.1 MB/s. Read speed is an average of 6.2 MB/s.

The whole time the MTU is set to 1492 sending a file that is 256 MB in size


He said if things were good he'd call me back and if not I wouldn't hear from him and he'd send those results off to hardware to take a look at. I did not hear back from him.

The Stig
 
http://www.smallnetbuilder.com/index.php?option=com_wrapper&Itemid=153

And that's over wired.

Incidentally the only NAS device I've had which I've been anywhere near happy with so far (and I actually understand networking so I don't have unrealistic expectations, but even then I found most NAS's crashingly slow) is the Thecus N5200, which in that test romps ahead of most. But then it's also one of the most expensive SMB NAS's around (~$650 without drives). And despite the cost the N5200 feels a bit cheap. It's been perfectly reliable so far, but the entire thing looks a bit "DIY".

If you want the convenience of a relatively hands-off home server and speed, until Microsoft releases Windows Home Server your best bet is a Mini + external storage if it has to be Apple, the Thecus, or get your hands a bit dirty with FreeNAS. Anything else is going to suck speedwise.
 
Data corruption?

I find the NAS USB drive so slow it's not really usable. Once, it actually corrupted the data. Fortunately it was a .dmg file, and the corruption was caught when I tried to open it. When I transferred the same file from the first computer to the second via normal wireless (using the "n" protocol), there was no corruption and it was much faster. Another thing I've noticed is that transferring one large file via NAS is a lot faster than transferring the same amount of data in many smaller files. In any case, the corruption only happened once, so I can't absolutely say the NAS drive is unreliable unless others have experienced the same problem.
 
Yep, getting the same exact speeds on my Airport Extreme. (Running in N-only 5GHz) ~4.3 Mbps read and ~2-3 Mbps write

Finder file transfers seem to be the slowest experience: a 1GB file takes about 7 minutes to write to the NAS HD. Copying off the drive took about 4 minutes for reading that same file.

I tried watching a movie (MP4 file 1.1 MBps stream) and it played decently well for 2 Hrs straight. It hiccuped 4-5 times where it dropped out for a second or two. As for High Def playback I haven't tried anything ridiculously long in duration. But a 1080p trailer (3 minutes long) copied to the NAS HD played back fine for me.

Except I had the following problem:
glhiii said:
Once, it actually corrupted the data.
Click to expand...

The video file that I transferred from my HD to the NAS HD, the Finder transfer corrupted the video where it stopped playing halfway through in Quicktime. The original source file still played fine. Transferring the file again yielded a perfect copy.
 
I haven't done any serious testing, but I just tried to copy an ISO image from the APD (AirPort Disk) and it indeed went at about 3 MB/s. However, I don't recall it being that slow when I was copying the file on there in the first place, from a Windows PC.

The Windows PC was connected via Ethernet. The Mac is connecting wirelessly to a base, which is then connected via Ethernet to the AirPort.
 
Rob from Apple e-mailed me again and wants me to run a test. He said:

" We are still investigating your issue of slow drive performance when
connected to the Airport Extreme Base Station.

We need to gather some information of the drive when directly connected to your mac.
Please connect your HD to the mac directly and double click on the capture data script,
run it, and email me the resulting file(s). This will give us an idea of the drive block size
and format information."

The file attached is called "CaptureData_7.1.2.dmg"

I ran it and it seems to take down detailed information about your system. I sent him the results. I will call and speak with him today I hope.

If anybody wants this program PM me with your e-mail and I'll e-mail it to you.

The Stig
 
Expecting 10-15mbps over wireless when you get 16-18 over wired is unrealistic. USB has a transfer rate of 480mbps, but Apple only touts "up to" 250mbps for its airport base, so you should be expecting no more than 8mbps as a maximum for your rates. That being said, yes, 2-3 sounds a bit low.
 
kyleaa said:
Expecting 10-15mbps over wireless when you get 16-18 over wired is unrealistic. USB has a transfer rate of 480mbps, but Apple only touts "up to" 250mbps for its airport base, so you should be expecting no more than 8mbps as a maximum for your rates. That being said, yes, 2-3 sounds a bit low.
Click to expand...
I don't think the slowness has anything whatsoever to do with the wireless vs. wired, but rather with the NAS (Network Attached Storage) translation that must take place inside of the base station, and it does not seem unreasonable at all to me for a multipurpose consumer device like this. Sure, a powerful file server can do the translation easily, but asking the same thing of the processor in the Airport Extreme is asking a lot. You are asking it to translate from a file-based ethernet protocol to a file-system to a block-based disk protocol, and that takes some umph. Just take a look at consumer-level NAS devices on the market, and 2-3MBps is reasonable for this price range.
 
FINAL UPDATE:

Rob from apple called me back. He says there isn't anything more they could do. He also said they know of the issue and they have had other people having the same issue. So I said I wanted a refund and he said I'd have to call the My Apple.

So I called them. They were easy to take it back but wanted me to pay 10% for restocking or something like that. I don't really see how this is my fault and it isn't like I just don't want it. It doesn't work as promised. I explained that to him, he put up little fight about it and spoke with a manager and they were going to wave that for me. Great. Then he tells me I'd have to pay for shipping. Again not seeing why I should pay for shipping on it because like I said I've been working with tech support since I got it to fix the problem and that it isn't my fault. So, I complained a little bit and explained and he put up a bigger fight about it. So I asked to speak to his manager. He put me on hold and came back in a minute or two without a manager and said they will send me the shipping labels too. So I'm getting a full refund.

So, it is finished. I'm sending back the base station. I do like it. Everything else about it is great, but for the USB hard drive is really what I got it for. Without that part working great, there isn't really reason for me to have it. At least no reason to spend $204.00 CAD on it anyway.

I agree that maybe it just won't work. Either a NAS problem or something else. Thank you all for your input. I just wish I knew that before buying the base station and I wouldn't of got into this mess.

So be warned when buying the new base station. If you don't care about the slow HD then go for it! If you do, maybe you need to look at different options to go with it, or just go without it.

Thanks everybody,

The Stig
 
Too bad. :mad:

I was going to purchase the new AirPort for the same reason as you.
Now I think I'll just use an ethernet network drive.
 
lancestraz said:
Too bad. :mad:

I was going to purchase the new AirPort for the same reason as you.
Now I think I'll just use an ethernet network drive.
Click to expand...

I feel you man. I'm really disappointed. I'm just going to use my HD through firewire. A ethernet HD would be a better idea.

Now, I don't know. Maybe it would be pretty fast going through a ethernet drive over N. But as my tests show networking through a PC it isn't faster. So maybe it wouldn't work. I haven't tested it. The base station is only 10/100, so going with a ethernet drive through ethernet on a 1000 router would be better.

The Stig
 
lancestraz said:
Too bad. :mad:

I was going to purchase the new AirPort for the same reason as you.
Now I think I'll just use an ethernet network drive.
Click to expand...
Unless you pay several times the cost of the base station, you will still get very slow speeds. It's just the nature of the beast. If you have an extra computer that you can use as a file server that will be much faster, because the computer has enough processing power to provide faster speeds. Good luck with your search.
 
The Stig said:
I feel you man. I'm really disappointed. I'm just going to use my HD through firewire. A ethernet HD would be a better idea.

Now, I don't know. Maybe it would be pretty fast going through a ethernet drive over N. But as my tests show networking through a PC it isn't faster. So maybe it wouldn't work. I haven't tested it. The base station is only 10/100, so going with a ethernet drive through ethernet on a 1000 router would be better.

The Stig
Click to expand...
Would this setup result in 1000 speed?
Laptop connected wirelessly to AirPort Extreme (pre N version).
1000 ethernet switch connected to AirPort.
Ethernet hard drive connected to switch.

Common sense says no, but I though I read somewhere that you could.

danny_w said:
Unless you pay several times the cost of the base station, you will still get very slow speeds. It's just the nature of the beast. If you have an extra computer that you can use as a file server that will be much faster, because the computer has enough processing power to provide faster speeds. Good luck with your search.
Click to expand...
Wait... So I could plug a USB HDD into a spare Mac and then use that HDD with Leopard's Time Machine?
Could I also partition the HDD and have one partition for junk and another for Time Machine?
 
lancestraz said:
Wait... So I could plug a USB HDD into a spare Mac and then use that HDD with Leopard's Time Machine?
Could I also partition the HDD and have one partition for junk and another for Time Machine?
Click to expand...
Probably so. Nobody really knows how Time Machine will work until it comes out, but if you can map storage from the network to your computer that is probably all that it takes. And it wold certainly be faster than a USB drive attached to the AEBS.
 
lancestraz said:
Would this setup result in 1000 speed?
Laptop connected wirelessly to AirPort Extreme (pre N version).
1000 ethernet switch connected to AirPort.
Ethernet hard drive connected to switch.

Common sense says no, but I though I read somewhere that you could.
Click to expand...

I have no idea. I've pretty much given up on the idea. Firewire it is for me. It is good and fast.

The Stig
 
Ethernet attached NAS also slow

lancestraz said:
Has anyone tried using a HDD that connects via ethernet? Not USB.
Click to expand...

Yes. I have. I have my Maxtor Shared Storage Plus 500 GB connected directly to my AE on one of the ethernet ports.
Right now I'm moving 17 GB from my Maxtor to my MBP. It is steady at 3.1 MB/s. It is faster than when I used a -g base station, which gave me around 2.0 MB/s. But still a huge disappointment, as I expected to max out the 100 MB/s interface with my new AE.

I agree that it is probably too much too expect the AE to deliver 300 MB/s when transferring from a USB drive, as the controller in the AE then must work really hard to translate, but why is my Maxtor slow? After all it already communicates through Ethernet. All the AE needs too do is put it on -n!

When I connect my MBP to my AE throught ethernet cable I get speeds from the Maxtor up to 4.85 MB/s.

And I have managed to get 11.25 MB/s between a PC connected by ethernet and my MBP connected by -n

Can somebody please explain why the AE is slow when transferring from my ethernet attached Maxtor? :confused:

By the way Apple: Rethink your "It just works" slogan. IT DOESN'T! :mad:

Oyvind
 
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