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stuff about puters

Month: December, 2016

UPaxos: Unbounded Paxos Reconfigurations

The year 2016 turned out to be a bumper year for pragmatic Paxos discoveries. Hot on the heels of the FPaxos discovery of more flexible quorums comes Unbounded Pipelining in Dynamically Reconfigurable Paxos Clusters or “UPaxos”. This uses overlapping quorums between consecutive cluster configurations, and a leader “casting vote”, to enable cluster reconfigurations in a non-stop manner even when reconfiguration messages are lost. Read the rest of this entry »

Paxos Reconfiguration Stalls

In a previous post I covered using the Paxos engine itself to do cluster reconfiguration as per the 2001 Paxos Made Simple paper. In this post I will cover a problem with that technique know as pipeline stalls. This post is to set the scene for a new technical report published 2016 which fixes the problem with a state-of-the-art Paxos implementation called UPaxosRead the rest of this entry »

Just say NO to custom hardware for Paxos 

Today’s Morning Paper on “Just say NO to Paxos overhead: replacing consensus with network ordering” was a thrilling disappointment. It’s always with both excitement and trepidation I read about new developments in distributed consensus; is today the day that I learn that Paxos is obsolete? The NOPaxos paper (“network ordered Paxos”) reviewed at the link above has a title which suggests a breakthrough. Unfortunately, it has far less general applicability, and far higher economic cost to implement, than “vanilla” Paxos.

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