On Sun, 22 Jul 2001 at 08:03, Steve Lord wrote:
> 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.
Yes, this is what I was referring to. I was under the impression that this
was "bad", though, and one effectively "lost space". Are inodes allocated
dynamically for large files different from those allocated dynamically for
a bunch of small files? Meaning, if inodes are allocated for a large file,
then the large file is deleted, and the inodes are not returned to free
space, will filling up these allocated inodes with small files be "bad" or
would filling up the free space with small files (thus creating inodes for
them) have had the same effect anyway?
> 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.
This is great! Perhaps we could have this information in the XFS FAQ under
something like "when is my disk nearly full and what happens when it's
nearly full"?
Thanks a lot for the help! :)
--> Jijo
--
Federico Sevilla III :: jijo@xxxxxxxxxxxxxxxxxxxx
Network Administrator :: The Leather Collection, Inc.
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