On 10/18/2010 09:48 AM, Eric Paris wrote:
1) IMA uses radix trees which end up wasting 500 bytes per inode because
the key is too sparse. I've got a patch which uses an rbtree instead
I'm testing and will send along shortly. I found it funny working on
the patch to see that Documentation/rbtree.txt says "This differs from
radix trees (which are used to efficiently store sparse arrays and thus
use long integer indexes to insert/access/delete nodes)" Which flys in
the face of this report.
Radix trees can efficiently store data associated with sparse keys *as
long as the keys are clustered*. For random key distributions, they
perform horribly.
-hpa