The poor performance of my 1Gb lan

[Tom Yang]

Hi sir:
When I use performance Test 6.1 to measure my 1Gb lan,the average transmission is only 533944 Kbits/s(my test parameter is: transfer protocol:TCP,Send Data:fixed block size,my server and client all use 1Gb
lan),I don't know why did my lan have so poor performance.But when I use Iometer to perform this,the result is 110Mbytes/s,it looks the performance is correct.So could you give me some advice why did my lan have so poor performance when use performance Test 6.1 to measure it?
Thanks!

Tom

[David (PassMark)]

0.5Gbit/sec is actually not all that bad for a 1GB network.

It is impossible reach 1Gbit/sec with TCP/IP becuase of the protocol overhead.

You should check the CPU usage as maybe your CPU(s) are too slow to recieve or transmit the data. It might also a bottle neck on your PCI bus (assuming these are PCI cards). And there are a whole bunch of Windows configuration settings in the registry that might slighly improve performance. (Sliding window sizes, MaxMTU sizes, etc..). Plus you might also find you have other network devices slowing things down, e.g. switches and routers that claim 1Gbit but can't actually do it or other traffic on the LAN segment. Oh and don't forget the cabling. Get quality Cat-6 if you can.