Regular xzutils now does multiple threads with the -T option.
> -----Original Message-----
> From: Ramon Fischer <ramon_fisc...@hotmail.de>
> Sent: Sunday, September 26, 2021 5:23 AM
> To: gentoo-user@lists.gentoo.org
> Subject: Re: [gentoo-user] How to compress lots of tarballs
>
> In addition to this, you may want to use the parallel implementations of
> "gzip", "xz", "bzip2" or the new "zstd" (zstandard), which are "pigz"[1],
> "pixz"[2], "pbzip2"[3], or "zstmt" (within package "app-arch/zstd")[4] in
> order to increase performance:
>
> $ cd <path_to_mounted_backup_partition>
> $ for tar_archive in *.tar; do pixz "${tar_archive}"; done
>
> -Ramon
>
> [1]
> * https://www.zlib.net/pigz/
>
> [2]
> * https://github.com/vasi/pixz
>
> [3]
> * https://launchpad.net/pbzip2
> * http://compression.ca/pbzip2/
>
> [4]
> * https://facebook.github.io/zstd/
>
>
> On 26/09/2021 13:36, Simon Thelen wrote:
> > [2021-09-26 11:57] Peter Humphrey <pe...@prh.myzen.co.uk>
> >> part text/plain 382
> >> Hello list,
> > Hi,
> >
> >> I have an external USB-3 drive with various system backups. There are
> >> 350 .tar files (not .tar.gz etc.), amounting to 2.5TB. I was sure I
> >> wouldn't need to compress them, so I didn't, but now I think I'm
> >> going to have to. Is there a reasonably efficient way to do this? I
> >> have 500GB spare space on /dev/sda, and the machine runs constantly.
> > Pick your favorite of gzip, bzip2, xz or lzip (I recommend lzip) and
> > then:
> > mount USB-3 /mnt; cd /mnt; lzip *
> >
> > The archiver you chose will compress the file and add the appropriate
> > extension all on its own and tar will use that (and the file magic) to
> > find the appropriate decompresser when you want to extract files later
> > (you can use `tar tf' to test if you want).
> >
> > --
> > Simon Thelen
> >
>
> --
> GPG public key: 5983 98DA 5F4D A464 38FD CF87 155B E264 13E6 99BF
>
