Really Slow Transfer from Windows

Hi Guys,
I'm trying to upload some data from a server running windows 2003 server standard edition to a debian box. Both are running core 2 duo processors in a 1gbps switched environment. Problem is I'm only getting about 30KBps upload speed, I really need at least 5MBps. Testing from other windows and linux clients the speeds are far higher. What could be the problem?

Maybe this FAQ may give you some hints.

That FAQ doesn't help. My CPU is being used at about 10% and the upload is being capped at 100KBps. In fact it's being capped on multiple windows machines at about 100KBps. From a Linux machine, through all the same routers, the performance is closer to 600-700KBps, about the limit of our connection. Downloads also appear to have a limitation, but at about twice the speed.

Any ideas?

I've found that even when my CPU usage is ostensibly low (as reported by task manager, for instance), switching to Blowfish improves transfer speeds quite a bit. So if you haven't tried that, do.

The computers I use at home are fairly new and fast, but my "network" consists of a Linksys at 100Mb, and I usually see ~30-40Mb/s (or 4-5MB/s if you prefer) transfer speeds. It's half what I should be getting, but it's "good enough" and I blame the Linksys.

At gigabit connection speeds, the receive window limitations identified in other forum threads will be even more crippling. That's part of the underlying PuTTY code, and the improvements will be seen in WinSCP once they are made in PuTTY. But even so, you should be easily doing better than 5Mb/s.

Also... as noted in the other forum thread, try using scp instead of sftp. When I transfer to/from *nix hosts, scp is much faster, even though there's essentially no speed difference between scp and sftp for me between Windows hosts.

Disabling compression is probably advisable in your situation, as the time to compress and send the data is likely longer than the time to just send it uncompressed (if you really have a Gbit path through your network... but that doesn't jive with the 5.5Mb/s limitation you alluded to).

TS wrote:

Also... as noted in the other forum thread, try using scp instead of sftp. When I transfer to/from *nix hosts, scp is much faster, even though there's essentially no speed difference between scp and sftp for me between Windows hosts.

Disabling compression is probably advisable in your situation, as the time to compress and send the data is likely longer than the time to just send it uncompressed (if you really have a Gbit path through your network... but that doesn't jive with the 5.5Mb/s limitation you alluded to).

I'm my case I've tried Blowfish (no real change), checking if compression was on (it wasn't), and trying scp vs sftp (no real change). It seems to be unrelated to any of that or the particular machine, since Windows Vista installs and Windows XP installs are seeing the same limitation (or cap, if you will) in performance through WinSCP that isn't seen when a command line tool is used on a couple of Linux boxes (to the same server).

This issue has been added to tracker.

hi!
using SCPtool we can easily transfer files from Unix to windows, but can we use it to transfer files from windows to windows?
Please reply asap
its urgent!!!!!!

Thanks in advance
vipul

vipul wrote:

using SCPtool we can easily transfer files from Unix to windows, but can we use it to transfer files from windows to windows?

You need SSH server on the other side. This guide shows you how.