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Message-ID: <40F3CD18.9090208@alexisgallagher.com>
Date: Tue, 13 Jul 2004 12:52:56 +0100
From: Alexis Gallagher <alexis AT alexisgallagher DOT com>
Reply-To: alexis AT alexisgallagher DOT com
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To: Steven Hartland <killing AT multiplay DOT co DOT uk>
CC: cygwin AT cygwin DOT com
Subject: Re: rsync very slow, but not a network issue
References: <40F3BFC4 DOT 9060000 AT alexisgallagher DOT com> <009b01c468ca$217959e0$b3db87d4 AT multiplay DOT co DOT uk> <40F3C6CE DOT 6030602 AT alexisgallagher DOT com> <00b001c468cd$693f5880$b3db87d4 AT multiplay DOT co DOT uk>
In-Reply-To: <00b001c468cd$693f5880$b3db87d4@multiplay.co.uk>
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Ok,

Now this is progress. When I use '--size-only' then I do see a speedup. 
The 'transfer' is virtually instantaneous on the stopwatch, and 'rsync 
--stats' reports a speed of a mere 25 bytes/sec but with a reported 
speedup of 78125.

I can see why this works, but I remain confused why I should need to 
resort to it. This is basically dispensing with the rsync algorithm, no?

The cygwin machine is a Pentium III, 966 Mhz, 512MB of RAM. And the OSX 
machine is a 1 Ghz PowerPC G4 with 256MB of RAM. I can't believe 
everyone would use rsync as much as they do if it were not useful on 
machines of such specifications.

Is there a way to benchmark its hashing algorithm on both sides? Maybe 
the rsync process is getting insufficient priority on one side of the 
transfer? I remain

puzzled,
Alexis Gallagher


Steven Hartland wrote:

> Alexis Gallagher wrote:
> 
>> So it's taking much longer in real time when the file is already
>> there, which is exactly the situation where rsync is supposed to
>> accelerate teh transfer.
>> 
>> The cygwin machine is a Pentium III 1Ghz, and the eMac is a bit
>> faster I believe. This should be fast enough that it's not
>> bottlenecking on the hash computation, I think.
> 
 > Are you using "--size-only"? Depending on the processor the check of
 > the file chunks can be slower.
 >


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