Andrew Pratt

Time Machine vs USB Drive vs Local Drive

I had a request to test the speed differences of copying a 700 meg file across the network to the internal hard drive in the Time Capsule router vs a USB drive plugged into the back of the router. I also decided to test the transfer speed of copying the file to the same external USB drive when it was plugged directly into my MacBook Pro. Here's the results...

Transfer from MBP to Time Capsule drive: 60 seconds
Transfer from MBP to External Drive plugged into Time Capsule: 215 seconds
Transfer from MBP to External Drive plugged into MBP: 30 seconds

This was a 700 meg AVI file that I was copying from my macbook pro across the network over gigabit ethernet to the 500 GB version of the new Time Capsule. The External Drive is a Vantec shell with a 200 gig 7200RPM Seagate drive installed in it that was connected to the Time Capsule and then my MBP via USB2.0. The Time Capsule also was updated to the latest firmware this evening.

As you can see the internal drive in the Time Capsule is MUCH faster then plugging in an external drive to the Time Capsule router. I'd expect the same results accessing an external drive plugged into an Airport Extreme as well. Going to a local drive plugged directly into your Mac though is almost twice as fast as going over the network. So... if speed is the most important aspect go local, if you need to share a drive the Time Capsule drive is pretty quick and is significantly faster then a USB drive hanging off the router so IMO the Time Capsule though slightly more expensive then buying an AirPort Extreme and a 500 gig USB drive is a better buy.

DaveF

Re: Time Machine vs USB Drive vs Local Drive

Do you mean "Time Capsule" (the AEBS + Hard Drive) when you write "Time Machine" (the backup software in OS X)? That is, should phrases like "External Drive plugged into Time Machine" be written as "External Drive plugged into Time Capsule"?

Andrew Pratt

Re: Time Machine vs USB Drive vs Local Drive

Yes Time Machine == Time Capsule. Its just the name I called the Time Capsule on my network but I can see where the confusion comes from.

DaveF

Re: Time Machine vs USB Drive vs Local Drive

Thanks for the clarification. I re-read your results and they made sense this time

This is surprising to me in many ways. First, I didn't realize that 802.11n was spec'ed (240 Mbps) to be nearly as fast as USB2 throughput (320 Mbps) -- and you're really seeing that speed.

I'm doubly surprised that it's one-quarter the speed when copying to an AirDisk on the TimeCapsule. That just doesn't make sense to me.

I'm considering a Time Capsule later this year, when my current TimeMachine-drive is full. So this was useful data for me.

Andrew Pratt

Re: Time Machine vs USB Drive vs Local Drive

Dave I wasn't transfering over N but gigabit ethernet. My testing was more to see what effect moving the drive inside the Airport case had over the external USB port more then testing N speeds. However....

Same file same conditions only this time over Wireless N

Internal drive: 125 seconds
External USB Drive plugged into TC: 285 seconds