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You are using rsync on local files. Rsync forces --whole-file whenver
it isn't networking.
On 10/06/13 16:03, Ole Tange wrote:> I use rsync on an SSD which is slow at writing, but very fast at
> reading, so it is important to me to avoid writing data.
>
> I had hoped rsync would only write changes in files when using
> --inplace, but it seems not:
>
> # Make a 1 GB file $ perl -e 'print "x"x1000000000' >
1g # rsync it
> (as expected this costs 1 GB writes) $ ./rsync-3.1.0/rsync
> --progress --inplace -cva 1g 1g.copy # Change the first 200 bytes
> inplace $ perl -e 'open(A,"+<",shift) || die; seek(A,1,1);
print A
> "a\n"x100;' 1g.copy # rsync again $ ./rsync-3.1.0/rsync
--progress
> --inplace -cva 1g 1g.copy
>
> I would have expected the final rsync to take 2 GB reads and 1 KB
> write, but it seems to take 2 GB read and 1 GB write (measured by
> /sys/block/sda/stat).
>
> Had it taken 2 GB reads and 1 KB writes it would have been much
> faster on my machine, as the 2 GB would be in the read cache.
>
> How can I tell rsync to write less given the situation above?
>
>
> /Ole
>
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Kevin Korb Phone: (407) 252-6853
Systems Administrator Internet:
FutureQuest, Inc. Kevin at FutureQuest.net (work)
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