Folcon

TickMerge: A Multi-Level Merge Consensus Algorithm for Commit-Anywhere Distributed Streams

Ben Gamble

Abstract

TickMerge is a consensus algorithm for distributed streaming systems that achieves global ordering through deterministic merging rather than leader-based log replication. Existing consensus algorithms such as Raft and Paxos require a single leader to serialize all writes, creating a throughput bottleneck and an availability gap during leader elections. TickMerge eliminates the leader entirely: any node in the ring accepts writes to a local write-ahead level (L0), and a background merge process---coordinated by a circulating ring token---produces a deterministic global ordering across all nodes. The system separates the write path (Command) from the read path (Query) using a CQRS architecture with multiple storage levels (L0 through L-Merged), each providing progressively stronger consistency guarantees. Clients choose their consistency level per-read, ranging from local-only (L0) to

Rich Hickey on becoming a better developer

Rich Hickey • 3 years ago

Sorry, I have to disagree with the entire premise here.

A wide variety of experiences might lead to well-roundedness, but not to greatness, nor even goodness. By constantly switching from one thing to another you are always reaching above your comfort zone, yes, but doing so by resetting your skill and knowledge level to zero.

Mastery comes from a combination of at least several of the following:

	;; # EMULATING DATOMIC EXCISION VIA MANUAL DATA MIGRATION


	;; *************************************
	;; ## Introduction
	;; *************************************

	;; This Gist demonstrates a generic way to migrate an entire Datomic database
	;; from an existing 'Origin Connection' to a clean 'Destination Connection',
	;; while getting rid of some undesirable data and otherwise preserving history.

	(defn animate-value
	[start-val end-val duration]
	(let [decrement? (< end-val start-val)
	transmit-chan (chan)
	cancel-chan (chan)
	animation-interval 40 ;40 ms interval - 25fps
	steps (/ duration animation-interval)
	full-range (- start-val end-val)
	per-step (util/abs (/ full-range steps))
	state (atom start-val)

	(use '[datomic.api :only [q db] :as d])

	(def uri "datomic:mem://accounts")

	;; create database
	(d/create-database uri)

	;; connect to database
	(def conn (d/connect uri))

	""" A script to attempt the compression of written english
	to the chinese character set """

	import os
	from collections import OrderedDict
	from math import log
	import itertools
	from collections import Counter