PAulN wrote:
Hi,
I know this the linux list but I have an irix question..
I was wondering if someone could please explain the policy for inode
allocation
in an XVM environment. To maximize performance, I'd like to create a
scheme where
multiple file creates in the same directory are distributed across
volume groups. If necessary,
I can resort to creating the inodes in separate directories and
hardlinking them into the "proper"
namespace but it would be helpful to know what XFS is doing under the hood.
I've tried various tests to charaterize the behavior but still have yet
to fully understand
how it works. Could someone enlighten me?
Thanks,
Paul
Normal behavior is that an inode is placed in the same allocation group
as the parent directory. New directories round robin to the next
allocation group.
Exceptions to this are:
o when there is locking contention on the allocation group, or it
does not have reasonable space available. In this case the allocator
will move on to the next available allocation group.
o for filesystems of more than 1 Tbyte inodes can be kept in
allocation groups within the first 1 Tbyte to keep inode
numbers down within 32 bits. This can be turned off with
the inode64 option (except on 32 bit linux where inode
numbers larger than 32 bits are a bad thing).
Steve
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