Re: How to refresh degraded BTRFS? free space fragmentation, file fragmentation...

[Martin Steigerwald <Martin@lichtvoll.de>]

Am Sonntag, 9. Dezember 2012 schrieb Martin Steigerwald:
> Hi!
> 
> I have BTRFS on some systems since more than two years. My experience so
> far is: Performance at the beginning is pretty good, but some of my more 
> often used BTRFS filesystem degrade badly in different areas. On some
> workloads pretty quickly.
> 
> There are also some fs however that did not degrade that badly. These were
> some that have way more free space left than the ones that degraded
> badly. About 900 GB freespace left on my eSATA backup disk with BTRFS
> that is also quite new. About 80 GB left on my BTRFS RAID 1 local home disk
> where I can build debian packages or kernels and such without the restrictions
> NFS brings (root squash). These still appear to be fine, but I redid the local
> home one with mkfs.btrfs -n 32768 and -l 32768 not to long ago, but I
> think it was quite fine before anyway, so I might have overdone it here.
> This already points at a way to prevent some degradation BTRFS filesystems:
> Leave more free space.

I also do not use them regularily as in each day.

Backup disk just every two weeks or so.

Local home sometimes each day a week, then not at all for weeks.

-- 
Martin 'Helios' Steigerwald - http://www.Lichtvoll.de
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