File walking issue?

[Adnan]

I mean this response.....
Is it true?
Can somebody please shed some light on it...............



Andrew Liles wrote:

> I assume
> - the remote server is Win2K
> - the remote server does not have an rsync daemon
> - the remote server is accessed using Samba
> 
> The problem, I reckon, is that your entire set of files is being dragged 
> across the network to the local machine during the "building file list" 
> before it properly gets into copying files.
> 
> My simple understanding of what rsync does is this:
> Frist: Rsync works out what to send by firstly determining which files 
> exist on the source (this is a quick "ls" type operation).
> 
> Second: assume a file has an identical file size then rsync must examine 
> the file to see if it is the same. It does, in essence, by doing a checksum 
> on the file; I am not sure quite how rsync works, but let's assume it 
> divides the file into blocks and does a checksum on the first block of 
> bytes and compares that to the local copy's first block checksum.  How can 
> it do that on the remote Win2K?  If you machine has no rsync daemon then 
> your LOCAL machine needs to calculate the checksum for the REMOTE 
> file.  The checksum is small to transmit over the network, but if the block 
> is, say 100k, we incur a 100k(+a little bit) network transmission.  If the 
> file is actually identical then WHOLE file has to be transmitted before it 
> knows that that file does not need to be transferred!
> 
> So why use rsync if it is this "bad"?  Well much of the time (a) the remote 
> runs an rsync daemon so the client can ask the remote to calculate the 
> checksum, (b) the local can invoke on the remote a shell in which it can 
> invoke rsync.  In the case of Win2K and a Samba share you don't have this 
> possibility.
> 
> How should you solve it?  One way is to use "Cygwin" (www.cygwin.com) which 
> allows you to run Unix commands (including rysnc) on a Windows platform.  I 
> use rsync CLIENT on a Win2K box fine.  What I have not tried is running the 
> daemon on the Win2K box.  Perhaps someone else can confirm this works ok.
> 
> 
> 
> At 18:43 16/02/2004, Max Kipness wrote:
> >Hello,
> >
> >
> >
> >I'm having an issue with one particular server and am hoping someone
> >here has dealt with this.
> >
> >
> >
> >I'm not sure whether this is a strictly samba issue or relates to the
> >way rsync walks the file list.
> >
> >
> >
> >Basically after mounting a Windows 2000 file system using and then
> >rsyncing the contents of this mount, it seems to take 5 - 8 hours to
> >complete. I've checked on the log periodically and determined that it's
> >the 'building of the file list' that is taking 95% of the time. We are
> >only talking about 140,000 files. I do many samba shares and not of them
> >have this issue. When doing a manual 'ls' command in various directories
> >on the mount, I encounter no slowness or anything out of the ordinary.
> >The samba log doesn't give much of a clue either.
> >
> >
> >
> >Has anybody come across this? Or does anybody have any ideas of how to
> >troubleshoot?
> >
> >
> >
> >Oh, and I'm using Rsync 2.6
> >
> >
> >
> >Thanks,
> >
> >Max
> >
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> 
>