confused about the slab_automove_decision function~

[shine]

hello，recently i read the memcached code of version 1.4.13.When i read
about the function of slab_automove_decision,i feel confused about
it,can you explain the main idea for me and tell me
something about the local variables like slab_winner and so on?Thank
you~my english is pool,if you
can not understand  what i describe,please tell me.I'm glad to accept
your reply。