On Fri, 2005-02-11 at 13:25 -0700, Abap wrote: > Hi, > > I noticed that my network seemed slow at times (when copying files). > I thought I would try to do a little investigation so that I could at > least get some baseline numbers for future comparison. > > What I have found is rather confusing to me (I know enough about > networking to barely be dangerous). > > I have 3 pcs hooked up together on a 100Mbs switch. Here is the basic setup: > > PC1 and PC2 have 100Mbs tulip based cards. > PC 3 has a 1 Gps gigabyte card using the sk98llin driver. > > I used iperf to test the speeds between various PCs. > > Here are the results using iperf: [snip] > All of the other combinations show results above 74 Mbits/sec. > > What has me confused is that I can transfer a file from PC1 to PC3 at > 73 Mbits/sec, but doing it in the opposite direction (PC3 to PC1), the > rate is only 323 Kbits/Sec (although it has been as high as 5.8n > Mbits/sec). > > Does anyone know why transferring files in one direction is 10 to 100 > times faster, or if there is some ofther testing I can do to narrow > down where the bottleneck is?
I've seen this where the network cards where set to auto/auto and the switch was forced at 100/full (it was a cisco switch). The network card automatically connected at 100/half. To fix we set the switch and cards to be 100/full. We also had some issues when both sides where set to auto/auto as well. Also remember to check your physical connections as well, it may be just a dodgy cable! -- [email protected] mailing list
