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View Full Version : slow file transfers -- why???




nymarty
Jan 20, 2011, 08:52 PM
Here's the setup... home network with a Trendnet Gigabit switch with an Apple Time Capsule in one part of the house and a Lacie Space Max NAS in the other. Both are wired Cat 6 to the switch. I'm using a Macbook Pro to wirelessly connect to the Time Capsule. From the MBP I'm initiating a file transfer of a 0.5Gb video file from the Apple Time Capsule to the Lacie. It copies the file but takes 12 minutes. Here's where it gets weird. When I then take the MBP and connect it via Ethernet to the switch (turning off wireless) and do the same file transfer, it takes 10 seconds. The MBP is normally used around the house where there is no ethernet connect which is why I'm trying to figure out this problem.

Why is it 12 minutes with one connection and 10 seconds with the other? Why are the files even going through the MBP? Is there another way to do this so the Time Capsule to Lacie or vice versa transfer is more direct and faster?

Thanks.

Marty



Dalton63841
Jan 20, 2011, 08:56 PM
Does the Lacie have any built in File Manager tools? Im not familiar with that. Also, are you connecting to the Lacie via AFP? Also, Are you connecting via Wireless G or Wireless N. Note that regardless a Gigabit network will be faster.

mmcxiiad
Jan 20, 2011, 09:37 PM
also, if you are connecting wirelessly with N but there are other devices connecting with G some routers will knock your N capability down to G.

nymarty
Jan 20, 2011, 10:59 PM
Thanks. I'm connecting to wireless with G because MBP that I have only does G. But I'm kicking off a file transfer that has nothing to do with the MBP and the 2 devices that are involved in the file transfer (Lacie and Time Capsule) are both on wired gigabit ethernet. I also tried putting MBP on wired LAN and was able to transfer .5Gb file to Lacie in 10 seconds and TimeCapsule in 10 seconds independently. So I know the gigabit ethernet is good and running at gigabit speeds. It's just when I have the wireless on the MBP that it does something to slow down the transfers. Just need to know what/why that is.

Thanks...

Marty

mmcxiiad
Jan 20, 2011, 11:13 PM
Thanks. I'm connecting to wireless with G because MBP that I have only does G. But I'm kicking off a file transfer that has nothing to do with the MBP and the 2 devices that are involved in the file transfer (Lacie and Time Capsule) are both on wired gigabit ethernet. I also tried putting MBP on wired LAN and was able to transfer .5Gb file to Lacie in 10 seconds and TimeCapsule in 10 seconds independently. So I know the gigabit ethernet is good and running at gigabit speeds. It's just when I have the wireless on the MBP that it does something to slow down the transfers. Just need to know what/why that is.

Thanks...

Marty

Marty

I am trying to understand this. You are using you macbook pro to initiate a file transfer from the lacie to the timeCapsule?

mmcxiiad
Jan 20, 2011, 11:16 PM
actually let me rephrase to see if I understand:

if you mac is connected via ethernet, then when you initiate a transfer from the lacie to the time capsule (or vice versa) speeds are great.

If you do the exact same thing if you are wireless, speeds are bad.

correct?

Dalton63841
Jan 20, 2011, 11:32 PM
But I'm kicking off a file transfer that has nothing to do with the MBP and the 2 devices that are involved in the file transfer (Lacie and Time Capsule) are both on wired gigabit ethernet.

Unfortunately the method you are using IS involving the MBP. As opposed to the normal flow:

Time Capsule --->Lacie

You are using the MBP to do the file transfer, so the flow then becomes:

Time Capsule--->MBP--->Lacie

So the MBP connection is important.

mmcxiiad
Jan 20, 2011, 11:34 PM
that was where I was going with this, I just wanted to make sure i understood the situation.

nymarty
Jan 20, 2011, 11:55 PM
Thanks. That's exactly what I'm doing. My question, then, becomes why? Why does the MBP become part of the transfer? Is there a way to do what I'm trying to do but not have the transfer go though MBP?

mmcxiiad
Jan 21, 2011, 12:54 AM
the reason why is your laptop has literally become the bridge between the two sharepoints. without your computer directing the traffic, all you really have is two dumb hard drives connected to your network - neither of which is has any ability to initiate, manage or even know what to do with incoming traffic once it arrives. How does the second hard drive know what the TCP/IP traffic is or where to put it? The missing component from this mix is a computer to not only say "I want to move this file from this location to the other location" but also to verify that the correct amount of data has been moved, and so many bits and pieces of the equation that we totally take for granted.

The ONLY way to have a file transfer is for a computer to manage the process. IF you are only going to do this once in a blue moon, then the easiest thing it to just plug an ethernet cable in and copy a few files.

On the other hand, if this is something that you are going to do frequently and the file size is going to get larger (I am assuming you are backing up your backups?) well then, my advice is to get another CHEAP computer that is physically attached to the network. Really any computer no matter how old will work just fine. If you don't have one and decide you are going to get one then get something that is VERY energy efficient. You don't need a monitor to manage this process. Remote into it. If it is a windows computer use Remote Desktop Connection (http://www.google.com/url?sa=t&source=web&cd=1&ved=0CCwQFjAA&url=http%3A%2F%2Fwww.microsoft.com%2Fmac%2Fremote-desktop-client&ei=CCo5TdL1JMOqlAehk73OBg&usg=AFQjCNFkAiYWQ40HKyxvPPAjxmhwVLHB1Q) or screen sharing on a mac (http://docs.info.apple.com/article.html?path=Mac/10.6/en/14065.html). Both are free and will work perfectly.

Now you use your laptop to remotely access the wired computer. This can be done wirelessly. The beauty of this is you have a wired computer initiate and manage the file transfer all at gigabit speeds. Once you start the process, you could immediately reboot your laptop and it would have absolutely no affect on the transfer. This because your laptop is now just being used to tell another computer what to do - the other computer is doing all the work. The other upside to this is you can log into that cheap computer from outside your network to initiate the transfer. Jut open up the right ports and you are golden.

Hope this helps.

nymarty
Jan 21, 2011, 08:05 AM
mmcxiiad --- GREAT explanation!

Thanks for taking me through how that works. I had always thought that the MBP was just initiating the transfer and that the drives could negotiate that from there but makes a lot more sense that it needs a controller to do that, in this case the MBP.

I like the recommendation. I just have to see if I have anything that fits the bill. Have an old imac but it's not gigabit ethernet. In the meantime, will put the MBP on a wired connect and remote into that from an iPad when doing these transfers.

Again, thanks!

belvdr
Jan 21, 2011, 02:26 PM
Have an old imac but it's not gigabit ethernet.

Even a 100Mb wired connection to a switch will greatly improve things over an 802.11g wireless connection.

Real connection speeds on 802.11g is roughly 20-30Mb, so you could see a potential 3-5x improvement in speeds with a move to 100Mb.

mmcxiiad
Jan 21, 2011, 02:32 PM
Even a 100Mb wired connection to a switch will greatly improve things over an 802.11g wireless connection.

Real connection speeds on 802.11g is roughly 20-30Mb, so you could see a potential 3-5x improvement in speeds with a move to 100Mb.

That is with theoretically ideal traffic. But if memory serves me, real world speed on 802.11g is 8-12. So yes, 10/100 ethernet would be a huge improvement. Also, since you aren't doing it from your computer, you could kick off the transfer process and walk away. if it takes a couple more minutes it has no baring on what you are doing on your laptop.

On the other hand, when you are transferring the data using your laptop (wireless) any and all other wireless traffic that you cause on your laptop (internet, email, other file sharing, etc) will cause the transfer speeds to slow and what ever you are doing to also slow down. This would be another benefit of using a wired computer, even if it is only 10/100.

nymarty
Jan 21, 2011, 02:50 PM
Thanks, everyone. I set up the MPB on the wired network and used the iPad to remote to that to start the transfer. It's much faster than it was before. Thanks for the great advice. I may even set up the iMac again on the network.

belvdr
Jan 22, 2011, 09:11 AM
That is with theoretically ideal traffic. But if memory serves me, real world speed on 802.11g is 8-12.

Theoretical/ideal for 802.11g is 54Mb. 20-30Mb is what I have observed in the real world. Now that is connection speed to the wireless network. The 8-12Mb is likely what you'll see for actually moving of data across that link, due to many factors including wireless being half duplex.

My example above was to give a bare minimum improvement spec. Going to 100Mb is likely to improve things well above the 3-5x I stated.