January 6th, 2004, 02:20 AM
Slow file transfer
I have two Mac G4s going through a a switch with two one gig ports and the transfer speed is very slow. When I connect them directly with a crossover cable, all is well.
The switch is connected to a one meg cable modem, no router.
Anyone know why the switch is slowing it down?
January 6th, 2004, 08:25 AM
Switch = ?
Very Slow = ?
Direct Connect Speed = ?
January 6th, 2004, 06:18 PM
Switch = ? Do you mean make model?
Very slow = As in estimated download time of a 67 m file of seven hours
Direct connect speed = same file down in minutes
More info: When I first set up sharing, I was using a 10 meg hub and realised the transfer speeds were unrealistic. I updated the hub to a switch, which has two one-gig ports, in the hope that this would fix it, but it's made no difference.
The older G4 has a 100 meg ethernet card and the new one has a one gig card. Clearly, when connected directly, they're capable of acceptable transfere speed, I'm just curious why the hub or switch slows the process to a snail's pace.
Never networked machines before. Thanks in advance.
January 7th, 2004, 05:58 AM
Yes, switch make and model. Is the file 67m bits or bytes?
January 7th, 2004, 10:31 AM
Sounds to me to be a buffer overflow issue that you will see with large file transfers when going from a 1000Mbps to 100Mbps as the faster NIC will over run the buffers in the switch causing the switch to defer packets and the sending machine to retransmit. when you connect with a cross-over cable the 1000 NIC will auto sense the connection and slow to 100Mbps so both machines are at 100Mbps. Try manualy setting the switch and two NIC's to 100 full. if you can not adjust the switch and it is in auto detect for speed and duplex it will cause framing errors as if you set one manualy both the switch port and NIC should be set static.
January 7th, 2004, 06:29 PM
Thanks for your kind and friendly response. That's 67 mbytes. Switch? Darn, I'm at the office right now, I'll check when I go home.
Thanks to you too. Both the switch and hub are very basic devices--no configuration control, as far as I can see. BTW, the data is going FROM the slow machine TO the faster one (if it makes a difference).
Would a router help? I have muliple machine permission from my ISP, so I didn't think I needed one.
Last edited by HnR; January 7th, 2004 at 06:31 PM.
January 8th, 2004, 06:24 AM
One other thing, what are you using for file transfer?
January 8th, 2004, 06:18 PM
Guess what? I was tired when I got home last night and clean forgot to check the switch details. It's 9:00 AM Friday here, I'll do it at the weekend for sure.
I'm using file sharing in OS X (panther).
January 9th, 2004, 07:32 PM
The device: Buffalo switching hub LSW-TS6GT2. It has six 100M ports and two 1000M. It says 'auto MDIX' on the facia. I have the two G4s connected through the fast ports (sorry if I'm stating the obvious).
Thanx in advance, guys
January 10th, 2004, 06:39 AM
FYI - I could not find any reference to the product you mentioned. Try connecting both machines to the 100M ports and see how it performs.