Creator of Raft Algorithm introduces LogCabin

Re:Creator of Raft Algorithm introduces LogCabin by alexnewman on Tuesday May 05, 2015 @12:52AM (#9490897)

Congrats, how does compaction work? I assume you can serve kvs from memory?

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Re:Creator of Raft Algorithm introduces LogCabin by ongardie on Tuesday May 05, 2015 @12:56AM (#9490913)

Compaction in LogCabin uses a snapshotting approach. It writes a header to a snapshot file, then forks off a child process to write the data into a snapshot. The data is just each node in the tree serialized as a protobuf using a pre-order traversal, IIRC. Much more detail on compaction [1] mentioning LogCabin explicitly.

LogCabin does currently keep all data in memory, so it never touches disk for read requests. It also keeps a copy of the entire log in memory for now, but I hope to address that eventually [2].

[1] https://github.com/ongardie/dissertation#readme

[2] https://github.com/logcabin/logcabin/issues/106

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Re:Creator of Raft Algorithm introduces LogCabin by alexnewman on Tuesday May 05, 2015 @12:53AM (#9490900)

Oh and can I call this from c easily?

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Re:Creator of Raft Algorithm introduces LogCabin by ongardie on Tuesday May 05, 2015 @12:58AM (#9490916)

There's not currently an extern "C" wrapper, but I don't think that'd be too much work to write.

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Re:Creator of Raft Algorithm introduces LogCabin by alexnewman on Tuesday May 05, 2015 @12:55AM (#9490908)

Oh and can I stop using zk now?

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