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The 1940s origins of Whataboutery

The exchange is indicative of a rhetorical strategy known as ‘whataboutism’, which occurs when officials implicated in wrongdoing whip out a counter-example of a similar abuse from the accusing country, with the goal of undermining the legitimacy of the criticism itself. (In Latin, this rhetorical defense is called tu quoque, or “you, too.”)

(tags: history language whataboutism whataboutery politics 1940s russia ussr)

etcd

A highly-available key value store for shared configuration and service discovery. etcd is inspired by zookeeper and doozer, with a focus on: Simple: curl’able user facing API (HTTP+JSON); Secure: optional SSL client cert authentication; Fast: benchmarked 1000s of writes/s per instance; Reliable: Properly distributed using Raft; Etcd is written in go and uses the raft consensus algorithm to manage a highly availably replicated log.

(tags: configuration distributed raft ha doozer zookeeper go replication consensus-algorithm etcd coreos)

_In Search of an Understandable Consensus Algorithm_, Diego Ongaro and John Ousterhout, Stanford

Raft is a consensus algorithm for managing a replicated log. It produces a result equivalent to Paxos, and it is as efficient as Paxos, but its structure is different from Paxos; this makes Raft more understandable than Paxos and also provides a better foundation for building practical systems. In order to enhance understandability, Raft separates the key elements of consensus, such as leader election and log replication, and it enforces a stronger degree of coherency to reduce the number of states that must be considered. Raft also includes a new mechanism for changing the cluster membership, which uses overlapping majorities to guarantee safety. Results from a user study demonstrate that Raft is easier for students to learn than Paxos.

(tags: distributed algorithms paxos raft consensus-algorithms distcomp leader-election replication clustering)