Is it normal that copying 1.7 TB of files from one external drive to another takes 2 days? (50GB took 1 hr so far.)
My MacBook 2009 is connected to external #1 via FW 400, to which external #2 is connected via FW 800.
Thank you!
Yes, that sounds quite normal. In fact reasonably fast for FW 400 speed.
Transfer speed is not only connect to size, but also to the number of files, which—gathered together—sum up 1.7 TB.
Otherwise, may be an initial ‘pessimistic’ estimation, it may take less, say 15 hours, maybe less.
The source drive and the target drive are connected via FW 800.
Can the Mac slow this transfer down only because the copy job is run from it?
From your post: "My MacBook 2009 is connected to external #1 via FW 400," This means the entire transfer chain runs at the speed of the slowest device in the chain, so yours is FW 400 unless you mistated the nature of the chain or I misunderstood your post.
Maybe I have a wrong notion of how this runs. I imagined that the files could be transferred from B to C at full speed, no matter what A comes before. There are no data to be transferred from the MacBook via the FW 400: all data are connected via FW 800. So I thought this should run at full speed, not at half. - Obviously, the MacBook is the bottleneck, as its OS transfers the data, no matter where they are stored. Is that correct? If so, my mistake. :-)
If you have multiple Firewire devices on a single chain then the transfer rate for the chain is determined by the slowest device. If your MacBook only has a FW400 port then no matter how fast those external drives are the data transfer rate is determined by the MacBook's FW400 port. Typically that might average 40 GBs/hour, but as has been stated by Cattus the transfer rate will be affected by how many files and how many really small files. Lots of the latter results in a dramatic reduction in throughput.
So, how many hours did it take?
Still running: 1 TB out of 1.7, 12 hrs left.
Estimation was correct, then. My idea was that it takes less time to transfer, say, 20 dmg images at 8 GB each than 1.6 TB made up thousands of tiles. It seems you have many small files.
Copying 1.7 TB = 2 days?
