1. I have two 4,1 Mac Pros with a 4 hard drive raid setup inside each computer which Reads and Writes at about 400 MB/s. When I transfer files between the computers with one ethernet cable connected directly from Ethernet Port 1 on each machine I get about 90 MB/s transfer. But when I connect Ethernet Port 2 on the machines with their own cable to my Airport extreme to get internet access I get speeds of about 10 MB/s. Is there a way to prevent the speeds from dropping without having to disconnect the ethernet port which is connected to the Airport extreme each time?
Gigabit Ethernet has a theoretical maximum of 125 MB/s (125,000,000 bytes per second - network and disk performance is measured in decimal notation, not MiB/sec).
In the real world, some of those bytes are used by protocol overhead, and some are lost to latency. I've seen real world disk to disk data rates of 110 to 115 MB/s using block protocols (CIFS, iSCSI).
You don't say what tools you are using to transfer the files - but 90 MB/sec (that is 90,000,000 bytes per second) is pretty good. (And if you're incorrectly using MiB/sec - 90 MiB/sec is about 94 MB/sec, which is even better.)
In other words, the best improvement that you could hope for is in the 10% to 15% range - probably not worth any great effort to improve. Will reducing a 60 minute file transfer to 55 minutes change your life?
And, WiFi always sucks compared to a copper connection. A shared bus subject to cross-talk and adjacent channel and other interference vs. a full-duplex point-to-point link to a crossbar switch.... When my husband and I remodeled our house, we put in one of the +500Mbps multi-band 802.11* access points - and Cat6 to every room (often multiple - there are 4 Cat6 copper drops in the kitchen). WiFi sucks - only visitors with Galaxies use it.
2. I was also wondering what is the fastest way to transfer large video files from one computer to the other. Is there any other method I could use to transfer files between the computers that would yield faster speeds than 90 MB/s?
Thanks!
Rob
If you want to spend a thousand or so dollars per port (to several tens of thousands) there are 10Gbps and 40Gbps and 100Gbps cards available. Probably not with Apple OSX drivers, though. And the switches cost more than most luxury cars. (I bought two switches, and a nice new car. Car was definitely cheaper.)