[CentOS] Sftp slow on both our centos installs

Tue May 1 16:57:17 UTC 2007
Ioannis Vranos <ivranos at freemail.gr>

Matt Martz wrote:
> 
> I did some quick research on google a few min ago.  Thinking back I have
> never seen higher than 2MB/s transfer speed using sftp between a Windows
> and Linux machine.  I have however seen much higher transfer speeds using
> sftp/scp between 2 linux machines.
> 
> A few people mentioned they believe the slowness is with the
> implementation of sftp/scp/ssh in the Windows app.
> 
> Try doing an sftp or scp transfer between the 2 CentOS machines and look
> at the transfer rate.  You could also try doing a transfer using Cygwin or
> maybe some other win32 ports.  However it may just be somehting strange
> with Windows.
> 
> ...While typing this I figured I would do some additional testing.  I
> downloaded VanDyke SecureFX (VanDyke has some of the best SSH
> implementations I have seen for windows).  My transfer rate was approx
> 10MB/s on a 100Mbit connection.  Whereas with WinSCP and FileZilla it was
> only approx 2MB/s


This message reminded me that Winblowz's (at least up to XP) network 
stack is optimised for dial up speeds, and required tweaking for 
broadband. Things like "TCP Window", MTU, and other stuff I don't 
remember now anymore. I suppose you have to tweak it by yourself, there 
was an app I was using for it on the net. Don't remember it though, but 
I think a Google search will give you it.


Ah, those glorious Winblowz days...