rsync - Sep 2006 - cygwin rsync performance and bandwidth between two w2003 servers

I have two Windows 2003 Standard Edition Server with 2x 3,0 GHz P4 and 4 
GB RAM.
On each server rsync runs as cygwin daemon (rsync version 2.6.6; 
protocol version 29).

The two servers are connected through a 2 MBit VPN link.
When I sync a single large file or a whole directory, rsync only uses 
50% of the available bandwidth.
When I do the same between windows and linux server, rsync takes the 
whole bandwidth.

Both windows and linux server have the same settings in rsyncd.conf.

Would be great if there is someone with any ideas how to solve this problem!

Thanks,
-- 
Sattler Media Press GmbH
Ulrich Jung
Kurt-Sattler-Stra?e 9 - 38315 Hornburg
Fon +49 5334 29 152
Fax +49 5334 29 344
mailto:ulrich.jung@wfw.de
http://wfw.de

Hi Quinn,

it's a local filesystem (SCSI U320)...
I tried it also with the --bwlimit switch but that doesn't matter - it's
still the same.
This morning I took a closer look at the transfer rate between w2003 and 
linux: unfortunally it's not the whole bandwidth but only 75% of it. And 
that's not protocol overhead or something like that because I checked it 
with iptraf on our proxy server. Only between two linux systems I'm able 
to get maximum speed.

Perhaps some more ideas?

Sattler Media Press GmbH
Ulrich Jung
Kurt-Sattler-Stra?e 9 - 38315 Hornburg
Fon +49 5334 29 152
Fax +49 5334 29 344
mailto:ulrich.jung@wfw.de
http://wfw.de


Quinn Snyder schrieb:
> Ulrich,
> 
> Just out of curiousity...
> What is the filesystem that you are trying to back up?
> Are you running a networked shared system or is it local through a SCSI or
> SATA interface?  If its networked, you may want to try the --whole-file
> switch.
> If you are indeed running a local system, just for kicks and grins, maybe
> try the --bwlimit switch.  I know that you are running a 2mb link between
> the two.  But you may want to try and tell your system what your
theoretical
> max bandwidth is.  For some reason it may only think it?s a 1mb link.
(don't
> know why, unless something is messy in the windows-linux transition).
> 
> Hope this helps.
> 
> Quinn Snyder
> Network Technician/Linux Administrator
> IP Phone: +1(602)748-4281
> q.snyder@frontiernet.net
> 
> -----Original Message-----
> From: Ulrich Jung [mailto:ulrich.jung@wfw.de] 
> Sent: Tuesday, September 12, 2006 4:49 AM
> To: rsync@lists.samba.org
> Subject: cygwin rsync performance and bandwidth between two w2003 servers
> 
> I have two Windows 2003 Standard Edition Server with 2x 3,0 GHz P4 and 4 
> GB RAM.
> On each server rsync runs as cygwin daemon (rsync version 2.6.6; 
> protocol version 29).
> 
> The two servers are connected through a 2 MBit VPN link.
> When I sync a single large file or a whole directory, rsync only uses 
> 50% of the available bandwidth.
> When I do the same between windows and linux server, rsync takes the 
> whole bandwidth.
> 
> Both windows and linux server have the same settings in rsyncd.conf.
> 
> Would be great if there is someone with any ideas how to solve this
problem!
> 
> Thanks,

Rob Bosch had similar performance problems on Windows and traced them
to highly fragmented files created by rsync.  I wrote a
quick-and-dirty patch to make rsync advise Windows of the eventual
file size in advance, allowing Windows to set aside a contiguous
region on disk; Rob found that it improved the performance
dramatically.  In case you want to try the patch, it is linked from
this message:
    http://lists.samba.org/archive/rsync/2006-August/016163.html

Matt