Date: Sat, 24 Apr 2004 14:07:37 -0700 (PDT) From: Don Lewis <truckman@FreeBSD.org> To: richardcoleman@mindspring.com Cc: julian@elischer.org Subject: Re: Testing Tar (was Re: bad news for bsdtar..) Message-ID: <200404242107.i3OL7b7E056981@gw.catspoiler.org> In-Reply-To: <408A9093.2050409@mindspring.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On 24 Apr, Richard Coleman wrote: > Don Lewis wrote: >>>>At least the -current version of tar skips reading the >>>>data when it is writing to /dev/null. >>> >>>A-ha! That explains a few of the odd timings I've seen. >>>I wonder why it does that? (Other than to look good on >>>benchmarks, of course. ;-) >> >> >> This speeds up Amanda quite a bit. Amanda will run tar with the >> --totals option as well as other options to specify either full or >> incremental backups multiple times for each file system that it backs >> up. It does this to plan the best mixture of full and incremental >> backups. If tar actually read the data from disk each time, the >> planning phase would take a *lot* longer, and would thrash the disk a >> lot more. > > Until libarchive gets support for sparse files, it's probably better to > stick with gtar or rdump with Amanda. The incremental backup capabilities that gtar has would be a lot more useful for Amanda than sparse file support. > But the concept of a version of Amanda that natively uses libarchive is > very cool. It seems like a natural target. Especially with ACL support.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200404242107.i3OL7b7E056981>