[plug] file transfer performance linux/windows and filezilla

[Shayne O'Neill]

wierd? SSh normally blows ftp out the water (ftp has a gnarly packet tax
from memory)

------------------------------------
"Must not Sleep! Must warn others!"
-Aesop.
Shayne O'Neill. Indymedia. Fun.
http://www.perthimc.asn.au

On Tue, 11 May 2004, Denis Brown wrote:

> Dear PLUG list members,
>
> Am I expecting too much "performance" from the ssh layer during secure file
> transfers?   To clarify...
>
> Linux (Debian GNU/Linux woody) transferring large files to/from Windows
> machines (NT4WS) over a 100Mb/s utp network with FileZilla as the Windows
> client.   Protocol is ssh(2).   Performance is woeful - like about 50Kb/s
> rising to 100Kb/s occasionally.   If I use ftp rather than ssh as the
> protocol, I get 7+ MBytes/sec so it looks like the network infrastructure
> is happy.
>
> NICs set to force 100Mb/s full duplex.   D-Link non-managed 10/100 switch
> (tried both 16-port and 5-port devices) both connected to the site LAN and
> disconnected from the site LAN.   MTUs set to 1500, sane-looking send/recv
> windows, buffer sizes, etc, etc.   FileZilla set to non- or compressed mode
> makes no difference to transfer performance.
>
> Linux -> linux using scp gives 10MByte/S so I assume there is some overhead
> in the ssh implementation.   Windows -> windows using only tcp/ip protocol
> stack and mapped drives gives probably close to wire speed.   On the
> windows side a netstat -e shows nothing obvious.   On the linux side,
> ifconfig likewise shows nothing apparently amiss.   Also "top" shows the
> linux boxes are not even thinking about raising a sweat.   Process ssh is
> taking maybe 9% cpu but these are fairly grunty machines.
>
> So... what level of performance (or performance hit) should I expect with
> ssh for secure transfers?   And importantly, are there any tuning
> parameters that can allow me to continue to use ssh without having my
> people drink lots of coffee waiting for their files to up/down load?   For
> example the ssh (login) client on Linux will accept a -c parameter to
> define which cypher is being used.   By default this seems to be
> 3des.   Blowfish is claimed to be a faster algorithm but I see no way (in
> FileZilla at least, or the associated PuTTY) of forcing a particular
> cypher.  In PuTTY on a session-by-session basis the preferred encryption
> algorithm can be set, but this doesn't seem to carry over to FileZilla.
>
> TIA,
> Denis
>
>
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