SMACK is a low-level I/O storage library which packs data into sorted blobs,
compressed with zlib, bzip2, or snappy.

It was created to host huge amount of rather small compressible data in
Elliptics, providing extremely fast write performance (tens of thousands RPS
per node with hundreds of millions already written objects); its backend
architecture was implemented with HBase in mind, but some changes were
tested and made different.

Data is compressed and sorted by key, that is, you get HBase-like scans for
free (although this is not yet exported to Elliptics API).

WWW: http://www.reverbrain.com/smack/