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From Benoit Perroud <>
Subject Simplified interface and non fragmentation work : Slab allocator and ByteBuffers
Date Wed, 18 Jan 2012 14:20:18 GMT
Hi All,

I worked on a slab allocation at some point, and while speaking about
separation of concerns, I tried to put both together.

Slab allocation basically means that the memory manager will point to
several slab, each one split in advance in slices of same size, let
say slab1 is composed of 1024 slices of 128 bytes, slab2 256 slices of
512 bytes and slab3 64 slices of 2048 bytes. When I try to store a new
byte array, I will search for the smallest slab that can fit the size
of the byte array, and store the content on this slice.

This is deadly simple to implement, fast at usage but the tradeoff is
some memory waste (if your size is not well sized for your business
you will have lot of unused bytes in slices).

Starting to implement the slab OffHeapMemoryBuffer, I start to find
overkill to have a Pointer object every time. Why not having a
MemoryManager layer that only deal with ByteBuffer. No expiration, LRU
and so on. This would be done by the Caching layer, where storing a
value will serialize it and store this alltogether in appropriate

Please give a chance to the attached patch that implement the
simplified MemoryManager layer, with Builder pattern style.



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