Re: defrag makes fragmentation worse

2011-10-12 Thread Chris Mason
Excerpts from Chester's message of 2011-10-12 00:14:21 -0400: On Tue, Oct 11, 2011 at 9:37 PM, Li Zefan l...@cn.fujitsu.com wrote: This confirmed my speculation. I've fixed this bug a month ago, but the patch hasn't hitted mainline. You can try it out:

Re: defrag makes fragmentation worse

2011-10-11 Thread Chester
On Tue, Oct 11, 2011 at 9:37 PM, Li Zefan l...@cn.fujitsu.com wrote: This confirmed my speculation. I've fixed this bug a month ago, but the patch hasn't hitted mainline. You can try it out: http://marc.info/?l=linux-btrfsm=131495014823121w=2 With this bug fixed, I think autodefrag won't

defrag makes fragmentation worse

2011-10-08 Thread Chester
Kernel 3.1-rc8 btrfs-progs-0.19 mount options: noatime,autodefrag (space_cache is enabled) There are snapshots present on the filesystem. When I do a btrfs fi defrag on a file, the file becomes much more fragmented. The end result can be a file with 20k times more fragments than before. Initially

Re: defrag makes fragmentation worse

2011-06-22 Thread Johannes Hirte
On Friday 10 June 2011 01:53:41 David Sterba wrote: On Fri, Jun 10, 2011 at 12:48:36AM +0200, Johannes Hirte wrote: I've observed several times that after a btrfs filesystem defrag a file was way more fragmented than before. For example, a file that was recently written, had 10 extents

defrag makes fragmentation worse

2011-06-09 Thread Johannes Hirte
I've observed several times that after a btrfs filesystem defrag a file was way more fragmented than before. For example, a file that was recently written, had 10 extents (output from filefrag). After a defrag filefrag showed more than 1900 extents. For curiosity, a simple copy of this

Re: defrag makes fragmentation worse

2011-06-09 Thread David Sterba
On Fri, Jun 10, 2011 at 12:48:36AM +0200, Johannes Hirte wrote: I've observed several times that after a btrfs filesystem defrag a file was way more fragmented than before. For example, a file that was recently written, had 10 extents (output from filefrag). After a defrag filefrag showed