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From: Alfred von Campe <alfred AT von-campe DOT com>
Subject: Re: rsync under cygwin too slow
Date: Mon, 23 Mar 2009 16:02:24 -0400
To: Vinod Gupta <vinod AT Princeton DOT EDU>
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> rsync -rtuplg --stats --verbose --progress --modify-window=2 / 
> cygdrive/c/localfolder /cygdrive/z/backups/
> ...
> ...
> The local and remote folders were already synchronized, that is why  
> 0 files were transferred. File list generation did take only 3  
> minutes but the whole process took more than 1.5 hours to finish  
> and consumed a whopping 1.9 GB of downloaded bytes and 0.4 GB of  
> uploaded bytes as per network counters. For what? Zero files, Zero  
> bytes of file data.

I'm pretty sure this is because rsync has to copy all the files  
locally to compare them to see if they need to be copied.  Try  
running the rsync as a service on the system that hosts the Z: drive  
(or run rsync over ssh to the system that hosts the Z drive) and you  
will see large performance improvement.

> As far as I can see, rsync under cygwin is also too slow to be useful.

This has nothing to do with Cygwin or rsync.  If you ran ROBOCOPY  
under Windows using the same setup you would see the same performance  
penalty.

Alfred


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