TripleD

TripleD copied to clipboard

Introduction:

    This is a very simple distributed file system borrowing many ideas from
    GFS.  The idea is to focus on simplicity and performance.  Not
    availability or fault tolerance (at all).

    Triple D:
            1) Dead simple...
            2) Done right...
            3) Distributed file system

Why:

    Tired of bullshit configurations and degraded performance?
    Want good performance?
    How about usable and understandable code?

Requirements:

    zeromq-2.1.7
    redis-2.2.7

Usage: master.py -- run on metadata master node worker.py -- run on worker nodes

    cptoddd.py      -- use to copy files into TripleD
    cpfromddd.py    -- use to copy files out of TripleD
    lsddd.py        -- use to list files in TripleD

Design:

    1) Master handles all metadata
    2) Workers are dumb trusting writes from clients
    3) Clients do RPC with master and workers directly
    4) Metadata comes from master, flows via client to workers
    5) Assume write once, read many in future; no append; no seek
    6) Client allowed to arbitrarily chunk (client knows best!)
    7) No replication right now; client would get list from master
    8) No multi-reading or multi-writing...
    9) All workers store chunks in the same path on their system
    10) Dumb round-robin assignment of chunks; worst case first node gets
        more data; last node gets least data
    11) Variable-sized chunks allowed
    12) No delete or rewrite

TODO: 1) master should only write into Redis on receipt of write info from a worker 2) concurrent writing to multiple nodes, reading from multi nodes (readahead as well)---basically add threading with push/pull sockets

Legal:

    TripleD is licensed under the MIT license.