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Elliptics network is a fault tolerant distributed key/value storage. The network does not use dedicated servers to maintain the metadata information, it supports redundant objects storage. Protocol allows to implement own data storage using specific features for the deploying project and generally extend data communication with infinite number of the extensions.
Eblob is an append-overwrite low-level IO library, which saves data in blob files. It supports fast append-only updates, flexible configuration of hash table size, flags, alignment and has an ability to lock in-memory lookup index (hash table) to eliminate memory swap.
Greylock is a C++ search engine which will take off the burden of the engine configuration, and yet be able to scale from hundreds to billions of indexed documents and from single to hundreds servers with as little as possible operations intervention.