Hi Roy,Almost all the traffic is on the forum - open discussion. Only one person posted to the mailing list. ;-) If done smartly, this may perhaps be possible, but the problem is the filesystem's metadata. Is this going to be dedup'ed? How much will this take? A simple backup will update atime on all the files backed up, and although atime isn't always wanted or needed, the problem occurs elsewhere.Typically the meta data on production systems is approx 10%~20% of the deduplicated stored data. Stored data is on my systems 40x less then the data written to the filesystem. For example, from a real life backup server making dozens of backups each day: # df -h Filesystem Size Used Avail Use% Mounted on /dev/cciss/c0d0p3 9.7G 2.4G 6.9G 26% / /dev/cciss/c0d0p1 99M 23M 72M 24% /boot tmpfs 7.9G 0 7.9G 0% /dev/shm /dev/cciss/c0d0p4 246G 6.0G 241G 3% /meta /dev/cciss/c0d1p1 274G 73G 202G 27% /blockdata /dev/cciss/c1d0p1 4.1T 1.5T 2.7T 35% /data lessfs 4.1T 1.5T 2.7T 35% /pooldata [root@lessfssrv pooldata]# du . -s -h 31T . [root@lessfssrv pooldata]# ls -alh /data/current/ total 314G drwxr-xr-x 2 root root 26 Jun 1 00:12 . drwxr-xr-x 6 root root 59 Jun 1 00:12 .. -rw-r--r-- 1 root root 314G Jun 22 14:26 blockdata.tch [root@lessfssrv pooldata]# ls -alh /meta/current/ total 1.4G drwxr-xr-x 2 root root 63 Jun 1 00:12 . drwxr-xr-x 6 root root 59 Jun 1 00:12 .. -rw-r--r-- 1 root root 1.3G Jun 22 14:52 blockusage.tch -rw-r--r-- 1 root root 89M Jun 22 14:45 dirent.tcb -rw-r--r-- 1 root root 89M Jun 22 14:52 metadata.tcb Mark.
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