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Re: Long running tar command

On Sat, Sep 28, 2024 at 02:39:29PM -0700, Bart Schaefer wrote:
> On Sat, Sep 28, 2024 at 2:52???AM Dominik Vogt <dominik.vogt@xxxxxx> wrote:
> >
> > On Fri, Sep 27, 2024 at 07:10:16PM -0700, Bart Schaefer wrote:
> > >
> > > The --verify pass won't happen until the output file is fully written,
> > > so is it really slower to run a second tar command to do that?
> >
> > I don't think it's slower, but tar has no way of verifying an
> > already existing archive.
>
> I believe
>   tar --compare -f dest.tar /data
> would be equivalent to --verify

Anyway, the discussed command has reduced the run time from about
6 hours to 2 hours and 20 minutes in comparison with the old
script that calculated the md5sum in a separate command.  That is,
after replacing "> dest.list" with "| gzip -9 > dest.list.gz".
Directly writing to the list file kept the disk head seeking all
the time, completely ruining performance.  (Backing up to a hdd.)

Ciao

Dominik ^_^  ^_^

--

Dominik Vogt
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