inefficient: --checksum calculation shouldn't be done for new files
Carlos Carvalho
carlos at fisica.ufpr.br
Sun Jul 3 18:12:48 MDT 2011
Jamie Lokier (jamie at shareable.org) wrote on 4 July 2011 00:00:
>Carlos Carvalho wrote:
>> When --checksum is used they're calculated in both ends to see if the
>> file should be transfered. This is of course not necessary if the file
>> doesn't exist in the destination. However, the checksum is still
>> calculated by the sender, which is often a very large overhead.
>>
>> Would it be possible to avoid it?
>
>Doesn't the receiver use the checksum to verify it received the file
>with no errors?
Yes, but this always happens, not only with -c. That checksum is
calculated during the download and has no overhead. The one with -c is
done before, just to decide whether to download.
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