Right Clicking Network File Very Slow Over VPN

Question

I am having real troubles with a VPN connection. The VPN connection is not used for a internet connection just for file browsing.

File browsing is slow, taking about 3-4 seconds to bring up a list of folders. I can live with this, however the problem is when I right click on a file. Sometimes the right click menu comes up instantly but sometimes it brings up the wait icon for anywhere between 30 seconds to a few minutes before displaying the menu.

I ran speedtest.net and the results were: 3.08 Down/0.13 Up (Mbps)

0.13Mbps = 16kbps upload. So I am not experiencing miracles with opening files. A 120kb file can take anywhere from 5 to 30 seconds. Sometimes transfering/opening files happens as expected other times its slow but the real issue is with the right click as mentioned.

Anyone have any ideas?

Using PPTP

Clients are all windows 7 pro

Answer 1

Have you any apps installed which have added context menu items to Explorer? WinZip, 7-Zip and others will do this. Try disabling any additional context menus and see if that resolves the issue.

Answer 2

SMB is somewhat of a "ping-pong-protocol" - it does a lot of interdependent back-and-forth communications for most of its actions. A Technet blog entry explains this quite colourfully:

If I wanted to copy a 1MB file over HTTP, it would look something like this over the wire:

Client:  HTTP GET /myfile.zip HTTP/1.0  
Server:  HTTP 200 OK, followed by 1MB of data

The only things that will slow down the HTTP transfer are a TCP window that is too small, slow start, and congestion avoidance.

The same transfer over SMB would look like this:

Client:  C SMB NT Create AndX myfile.zip  
Server:  S SMB NT Create AndX  
Client:  C Read AndX offset 0x0 data 0xf000  
Server:  R Read AndX (with 61440 bytes of data)  
Client:  C Read AndX offset 0xf000 data 0xf000  
Server:  R Read AndX (with the next 61440 bytes of data) 
(Repeat this another 16 times until we get 1MB of data)

So transfers and directory listings will not only depend on your available downstream bandwidth, but also greatly on the latency of your link and the bandwidth of your upstream connection. The same blog article recommends changing SizReqBuf on the file servers to 61440 as described in KB 320829 to somewhat alleviate this situation - this especially should help with speeding up directory listings.

Answer 3

This is going to sound weird, but we have seen slow Windows Share issues (directory displays, right clicking, etc..) if we did not disable "Automatically detect settings". This configuration setting is under Internet Explorer \ Tools \ Internet Options \ Connections Tab \ LAN Settings. With that setting disabled there is a remarkable difference when accessing file shares vie file explorer.