On Thu 2017-08-31 (09:05), Ulli Horlacher wrote: > When I do a > btrfs filesystem defragment -r /directory > does it defragment really all files in this directory tree, even if it > contains subvolumes? > The man page does not mention subvolumes on this topic. No answer so far :-( But I found another problem in the man-page: Defragmenting with Linux kernel versions < 3.9 or >= 3.14-rc2 as well as with Linux stable kernel versions >= 3.10.31, >= 3.12.12 or >= 3.13.4 will break up the ref-links of COW data (for example files copied with cp --reflink, snapshots or de-duplicated data). This may cause considerable increase of space usage depending on the broken up ref-links. I am running Ubuntu 16.04 with Linux kernel 4.10 and I have several snapshots. Therefore, I better should avoid calling "btrfs filesystem defragment -r"? What is the defragmenting best practice? Avoid it completly? -- Ullrich Horlacher Server und Virtualisierung Rechenzentrum TIK Universitaet Stuttgart E-Mail: horlacher@xxxxxxxxxxxxxxxxxxxx Allmandring 30a Tel: ++49-711-68565868 70569 Stuttgart (Germany) WWW: http://www.tik.uni-stuttgart.de/ REF:<20170831070558.GB5783@xxxxxxxxxxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
