Why is Windows file sharing so slow?

January 1, 2006 1:08 PM

Why is Windows XP workgroup file sharing so slow?

I've got a folder shared on my Windows XP computer (Computer A). It's connected to the network via a 100mb LAN card. Another computer (Computer B) is using an 802.11g wireless card, and a member of the same workgroup. If I'm sitting at Computer B and try to browse a folder on Computer A, it's extremely slow to even show folder listings and so on. If I try to highlight a file or drag it somewhere, it takes 20-30 seconds to respond to my mouse actions. Copying a 50-meg file takes about 25 minutes.

What can I do to improve this situation? A little Googling seems to indicate that Windows XP no longer uses NetBEUI for file sharing. Is their TCP/IP implementation of file sharing just that bad?

posted by pornucopia to Computers & Internet (7 answers total)

No. That's the answer to your question. Not to your problem, however. (And you're right that the old netbeui was faster. But this isn't your problem.)

It's not a probem going the other direction? Off the top of my head, I'd guess you have problems on the wireless side with either configuration or wireless. Are these the only two computers on your LAN? Can you connect them both via cabling to see what happens? You might use some of the relevant monitoring tools available for free from Sysinternals. Also, I'm thinking about windows browsing problems, which would show up with TCP/IP monitoring. A full-blown packet-sniffer will tell you what's going on, too.
posted by Ethereal Bligh at 1:53 PM on January 1, 2006

Response by poster: Ethereal -- I'll have to try the network transfer the other way too, I haven't done that yet. But given that Computer B has no other network slowness issues at all, is there any reason workgroup file sharing in specific would be a problem?

I'll try the network monitors too..
posted by pornucopia at 2:06 PM on January 1, 2006

One very common hack to speed up file browsing is to turn off the scanning of networked scheduled tasks.

1. Open up REGEDIT.

2. Navigate to: HKEY_LOCAL_MACHINE/ Software/ Microsoft/ Windows/ CurrentVersion/ Explorer/ RemoteComputer/ NameSpace/.

3. If you don't care about shared Printers, delete this key:
{2227A280-3AEA-1069-A2DE-08002B30309D}

4. If you don't care about shared scheduled tasks, delete this key: {D6277990-4C6A-11CF-8D87-00AA0060F5BF}

5. Navigate to: HKEY_LOCAL_MACHINE/ SYSTEM/ CurrentControlSet/ Services/ lanmanserver/ Parameters.

6. Edit the KEY "SizReqBuf" to the following:
0000ffff (make sure you select "dword").

7. Close REGEDIT. You're all set.
posted by Civil_Disobedient at 2:17 PM on January 1, 2006

"...is there any reason workgroup file sharing in specific would be a problem?"

I kinda expected an expert to have already come along by now, but I'll try to help a bit more. (I'm [no longer] even remotely a Windows Networking expert.)

Yeah, there are some reasons why it might be a more generalized problem that shows up most strongly with Windows file-sharing. There's a lot of cruft in windows file sharing and, for example, in the case of a marginal connection all this crap might push it over the edge.

There's a couple of things I'd do just as preliminary checks. Check the event for any relevant problems reported there. I'd remove any unneccesary stuff from your XP networking connection, leaving just tpc/ip and ms client and file sharing. I'd force NetBIOS on, lmhosts off (and, by the way, you almost always want to turn off "report this host's ip address to dns server"). From "explorer/tools/folder options", turn off "auto discover network pinters and folders". Remove the shares for everything but one test folder. (You'll still have the admin shares--you'd have to eliminate them with a tweak tool.) That will simplify things to the basics. If you still have the problem, then use one of those monitoring tools, or a packet sniffer like, heh, "Ethereal", to see what's happening and report it here if it's not sufficient for you to identify the problem.
posted by Ethereal Bligh at 2:47 PM on January 1, 2006

One reason that sharing may be slow is that you've configured your MTU size for optimal internet usage. This is done automatically by a number of "Speed your internet connection" type utilities. If you've used one of these on either computer, then you'll get this problem. Fixing MTU is not for the faint of heart though, so I'd check everyone else's solutions first.

Given that file copies are also slow, I'd discount it being a problem with the network shares. (I may be wrong, but my experience in these situations is that it takes an age to see the share and then copies the file at a good speed)

Find out what value you have in MTU in the adaptors under
[HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Tcpip\Parameters\
Interfaces\
for both machines.

I agree that It's most probably your wireless connection.

Other things to check include:

- Any software firewalls or virus checkers you have installed. Disconnect from the internet, switch these off, and then try it again.
posted by seanyboy at 4:01 PM on January 1, 2006

If your two computers have relatively static IPs (either assigned manually or via DHCP), on each computer, add the IP address of the other in the LMHOSTS and HOSTS files in C:\WINDOWS\SYSTEM32\DRIVERS\ETC\. While this may or may not fix your particular problem, it will speed up and increase the reliability of network lookups dramatically. Note that if either computer's IP address changes, these files must be updated or nothing will work with file sharing at all.

Alternately, you could manually install NetBEUI on XP. It's not interoperable with non-Microsoft systems, though. Note that NetBEUI is a very "chatty", broadcast-driven protocol and may actually slow down your wireless network.
posted by zsazsa at 10:18 PM on January 1, 2006

I should explain my first paragraph better. If your two computers are named foo, with IP address 192.168.1.100, and bar with address 192.168.1.101, in the LMHOSTS and HOSTS files on foo, add the line 192.168.1.101 bar. On bar, add 192.168.1.100 foo.

Also, at the end of the line you put into LMHOSTS, add the phrase #PRE. LMHOSTS will probably also not be already there on the computers; it will have to be created.
posted by zsazsa at 10:23 PM on January 1, 2006