On Wed, 7 Jan 2009, Craig White wrote: > funny thing is that amanda developers are adamant that you disable > hardware compression and use software compression instead.
Amanda devs are adament about a few things and aren't always correct Hardware compression on older technologies left a lot to be desired, however LTO hardware compression is fast and comparable to gzip/fast in terms of efficiency. > Obviously it takes longer and more cpu power to compress the files in > software before storing them on the tape and if you leave hardware > compression on and use software compression too, the files probably grow > in size. Modern tape hardware compression has a "step-aside" algoritm - output data is compared to input data on the fly and if there is no gain from compression then it's not used and the data is written directly to tape. > Commercial backup software just seems to always use hardware > compression. See above. Software compression was probably worthwhile when CPUs and disks could trivially outrun tape drives. That hasn't been the case for at least half a decade. AB ------------------------------------------------------------------------------ Check out the new SourceForge.net Marketplace. It is the best place to buy or sell services for just about anything Open Source. http://p.sf.net/sfu/Xq1LFB _______________________________________________ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users
