From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hubert Kario Subject: Re: BackupPC, per-dir hard link limit, Debian packaging Date: Tue, 2 Mar 2010 14:09:22 +0100 Message-ID: <201003021409.22441.hka@qbs.com.pl> References: <1267496945.9222.155.camel@lifeless-64> Mime-Version: 1.0 Content-Type: Text/Plain; charset=utf-8 Cc: Robert Collins To: linux-btrfs@vger.kernel.org Return-path: In-Reply-To: <1267496945.9222.155.camel@lifeless-64> List-ID: On Tuesday 02 March 2010 03:29:05 Robert Collins wrote: > As I say, I realise this is queued to get addressed anyway, but it se= ems > like a realistic thing for people to do (use BackupPC on btrfs) - eve= n > if something better still can be written to replace the BackupPC stor= e > in the future. I will note though, that simple snapshots won't achiev= e > the deduplication level that BackupPC does, because the fils don't st= art > out as the same: they are identified as being identical post-backup. Isn't the main idea behind deduplication to merge identical parts of fi= les=20 together using cow? This way you could have many very similar images of= =20 virtual machines, run the deduplication process and reduce massively th= e space=20 used while maintaining the differences between images. If memory serves me right, the plan is to do it in userland on a post-f= act=20 filesystem, not when the data is being saved. If such a daemon or progr= am was=20 available you would run it on the system after rsyncing the workstation= s. Though the question remains which system would reduce space usage more = in your=20 use case. From my experience, hardlinks take less space on disk, I don'= t know=20 whatever it could be possible to optimise btrfs cow system for files th= at are=20 exactly the same. >=20 > Cheers, > Rob >=20 --=20 Hubert Kario QBS - Quality Business Software 02-656 Warszawa, ul. Ksawer=C3=B3w 30/85 tel. +48 (22) 646-61-51, 646-74-24 www.qbs.com.pl System Zarz=C4=85dzania Jako=C5=9Bci=C4=85 zgodny z norm=C4=85 ISO 9001:2000 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" = in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html