> Hi everyone,
>
> I'm wondering if XFS has certain issues when dealing with a filesystem whose
> usage is nearing its capacity. I ask because I have a partition that's using
> XFS (of course) with a 32768b internal log and is mounted
> with "rw,noatime,nodiratime,logbufs=8,biosize=16,osyncisdsync". Its size is
> 53.74GB total, and is currently at 80% usage (43.20GB used, 10.54GB free).
> Total inodes used and free are not a problem in this case, though (only 1%
> used). I will still need to use more space on the hard drive in the near
> future, before I can delete some stuff and free up space.
>
> I remember with ReiserFS before (I have absolutely no idea if this still exis
> ts
> today) that there was a FAQ entry about a filesystem slowing down when it
> reached something like 85% usage. I hope this isn't an issue with XFS, but
> thought I'd ask anyway.
>
> Also, I remember with XFS before (in the mailing list) that there was an issu
> e
> about inode allocation where if you delete a large file and then start fillin
> g
> up the disk with a lot of smaller files you'll be wasting space. Or maybe vis
> e
> versa also. What's the current status of this? :)
>
> Thanks a lot for the great filesystem guys! :)
If you create a large number of files in XFS, inodes are allocated dynamically
for them. If you remove all the files, the inodes are not returned to free
space. On something like ext2 inodes are allocated at mkfs time and the space
is never available for anything else. This I think is what you were referring
to.
XFS will slow down doing allocations when it is really full, you are no where
near full, 99.x% full is nearly full. Basically XFS chops the filesystem into
allocation groups (1 to 4 Gbytes each), free space is managed independently
in each of these. The slowdown happens when you have to scan through lots of
allocation groups looking for space to extend a file. There is an in memory
summary structure which tells you if it is worth even looking in an
allocation group, so it is not a major slowdown - unless you have lots of
parallel allocation calls going on at the time.
Steve
>
> --> Jijo
>
> --
> Federico Sevilla III :: jijo@xxxxxxxxxxxxxxxxxxxx
> Network Administrator :: The Leather Collection, Inc.
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