Comparison of huge files ineffective?

[Kevin Korb]

Do not use --checksum.  It has an extremely limited use case.  Normally
it is much slower than simply re-copying everything.  --checksum means
checksum every file on both ends (even files that only exist on one end)
before doing anything else even if doing so causes a timeout failure.
--checksum is the only part of rsync stupid enough to leave one end idle
potentially for hours.

On 03/14/2018 10:14 AM, Heiko Schlittermann via rsync wrote:
> Kevin Korb via rsync <rsync at lists.samba.org> (Mi 14 Mär 2018 14:52:55 CET):
>> Your observation would be right if you are using --checksum which you
>> shouldn't be.  Otherwise, unless you are using --whole-file rsync will
>> use its differential algorithm to compare the files.  If you are using
>> --progress you will see it step through the file at a faster speed than
> 
> Ok, Thank you. I'll try to find the options they're using.
> 
> But, anyway, even with --checksum, why can't it run and checksum the
> file on both sides in parallel? If I understand your answer, then it
> does it in sequence, doesn't it?
> 
> 
> 

-- 
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