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Thread ID: 63405 2005-11-08 18:48:00 actual ethernet speed heni72847 (1166) Press F1
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403085 2005-11-08 18:48:00 what are the speed like for you guys when you copy files across your computers on 100mbit lan?
the max possible speed is ~12MB/s right? but when i transfer files across it's not even half the speed

i know my computer might have some other bottlenecks such as slow cpu (one of the comps is 500mhz) and other issues like my not so well configured samba
but i notice how when i copy my files from linux comp to xp comp it goes at around 500KB/s which is..painfully slow considering both comps got 100mbit card
i also notice how my linux machine's cpu isn't running at 100%, still some processing power left over
now i use SMBDownloader on my xp machine running at high priority to copy a single file across and sometimes if i'm lucky i can reach speed of nearly 4MB/s and when that happens my linux machine's cpu is going at 100% and samba daemon taking up most of the cpu cycles

now how can i make copying files that fast by only using windows to copy and not some other program.. or is everyone elses lan that slow too?

um..also in lan settings optimisation is set for performace and got zonealarm on xp computer..not sure if those effect anything 		heni72847 (1166)
403086 2005-11-08 20:09:00 I can see 12 MB/s (or closer to 11 MB/s) on a switched 100 MBps network.
This is using FTP with a linux box on one end as the server and a XP client (with the cheapo Realtek cards).

With Samba I'd typically see 80% of that figure.

Here's some things to consider:

1) Are you using a switch or a hub?
2) Are the cables of good enough quality?
3) Have you tried different drivers (or even different kernel) for the Liux box and windows too?
4) Read the Samba tuning section of the Samba how-to. Be careful though as I have seen corrupt data.
5) Check the duplex settings for your network cards.
6) Get an ethernet crossover cable and test with that.
7) Update Samba.
8) Try it will firewalls off. 		gibler (49)
403087 2005-11-08 20:25:00 oo.. a whole list of things to try~

switch or hub..well..going through a dse adsl router.. so is that more of a hub than switch? switch faster right?

didn't consider drivers..will do that


now.. main thing i don't understand is how come that if it want to it can reach a higher speed..but under normal operations it decides to go slowly.. 		heni72847 (1166)
403088 2005-11-08 20:35:00 Definitely use a switch. You get one cheaply for under $100. Connect you PCs and ADSL Router to it. KiwiTT_NZ (233)
403089 2005-11-08 23:24:00 so the four ethernet prots on my router works like a hub not a switch?
why can't they just make the router work like a switch too instead of hub.. 		heni72847 (1166)
403090 2005-11-09 00:25:00 You will never, ever, get 12 MB/s . There are overheads .

The CPU speed has very little to do with file transfer speeds . Big multi-gigabit
routers use 600 MHZ Pentiums . IBM PCs, with 4 . 77 MHz 8088 processors , could happily use 10 MHz Ethernet .

A switch won't be faster than a hub at transferring files from one computer to another if there is no other traffic from other hosts on the LAN . If anything, the switch will be slower . ;) That's because it adds some latency: the switch "stores and forwards" packets, whereas the hub just regenerates them .

Run Ethereal or tcpdump on one of your other computers, and look for collisions or other reasons for repeated packets while you are doing file transfers . 		Graham L (2)
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