https://github.com/dormando/memcached/tree/slab_boost (the branch is here since it's not been merged into mainline yet)
I've made some small modifications to the slab rebalancing system to make it more aggressive. You can now reassign memory between classes all you want, compared to having to wait for a class to use up all the new items you just moved to it. The rebalancer and automover are now actually separate threads, instead of separate processes in the same thread. The rebalancer waits for a kickoff from a "slabs_reassign" command and immediately chews through memory. This command may be kicked off manually, via the slow automover (now known as automove=1), and via a new pants-on-fire "move slab page on first eviction" mode (automove=2).
memcached v1.4.13-slab_boost with slab_reassign,slab_automove=2
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