[SOLVED] Slow LAN speed; friendly suggestions?

[Pyneappel]

My small home network is based around a Netgear C7000 cable modem/router. I have a laptop, Android devices, and IoT devices connecting via WiFi. I have two desktops--one Linux and one Windows 7sp1 both with a wired connection. Everything is set up out-of-the-box. I haven't ever attempted any tuning or anything. the desktops and the router all say they support gigabit ethernet.

All devices seem to connect to the internet at expected speed to me; download speeds somewhere around 200 mbps on the wired and 5G WiFi, and a bit slower on the 2.4G. This is what I would expect given my ISP plan.

When I copy files via USB3 onto the desktop internal drives I get 100-200mBps transfers.

However, when I try to transfer files over the LAN between the two desktops, I seem to get only about 10-11 mBps.

Linux is sharing via Samba, and Windows is using whatever the default is for Windows shares. It seems to make no difference in which direction I do the copy and whether I am reading or writing.

I tried a few things like disabling "Windows Auto-Tuning" but that had no effect. I don't really want to stumble around in the dark changing all sorts of settings with no real idea of what I am changing or why.

can anyone point me in a more targeted direction of what might be going on here? Where WAN speeds are as expected but inter-computer file transfer on a gigabit local LAN is only 10 mBps?

Thanks.

 

[QwerkyPengwen]

Do you happen to be running a 5400rpm drive on one of the PC's?

 

[bill001g]

Can be many things but the best first test of lan is to use a old line mode tool called IPERF. It likely is already installed on linux and you can download it for windows.

This is a very very simple program that tests the lan hardware and drivers. It is not affected by things like cpu/memory or disk. You generally see 900mbps transfer rates in both directions.

This is mostly to cut down the things you check. After this I would try to use FTP to transfer files and see if it runs different than samba.

Also be aware you will see massive difference in speed if you transfer 1 large files compared to many tiny files. In some cases the file name and directories are larger than the data itself.

 

[Pyneappel]

Do you happen to be running a 5400rpm drive on one of the PC's?

7200rpm and SSDs.

 

[Pyneappel]

the best first test of lan is to use a old line mode tool called IPERF

Thank you! IPERF helped me isolate the issue to the Windows desktop. I don't know root cause yet--drivers? cable?-- but it definitely focused my direction.