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Paper summary. CORFU: A shared log design for flash clusters

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By: Mahesh Balakrishnan, Dahlia Malkhi, Vijayan Prabhakaran, Ted Wobber, Michael Wei, John D. Davis, Appeared in NSDI'2012
This paper applies VPaxos ideas (of using an auxiliary Paxos box for reconfiguration) and chain replication ideas in the context of Flash SSDs. The vision is that Corfu's novel client-centric design eliminates storage servers in favor of simple, efficient and inexpensive flash chips that attach directly to the network. The clients directly write to storage nodes, similar to what happens in Dynamo/Cassandra/Voldemort replication, but linearizability is still guaranteed.

Previously I had summarized the Tango paper, for maintaining distributed data structures over a shared log. Tango builds on the Corfu log abstraction.


Corfu involves three main functions:

A mapping function (maintained at the VPaxos box) from logical positions in the log to flash pages on the cluster of flash unitsA tail-finding mechanism (using a sequencer node) for finding the next available …

Dissecting performance bottlenecks of strongly-consistent replication protocols

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Dissecting performance bottlenecks of strongly-consistent replication protocols
Ailidani Ailijiang, Aleksey Charapko, and Murat Demirbas.

Hey, this is our paper! This appeared in Sigmod 2019 couple weeks back. This paper came out of the dissertation work of Ailidani Ailijiang. He has build the Paxi framework in Go, available on GitHub, to prototype any Paxos flavor quickly. His dissertation is called: "Strongly Consistent Coordination for Wide Area Networks". 

Writing blog posts about one's own papers is harder than writing posts about others' papers. When you write a summary of your work, you want to include everything, and cannot detach yourself from specifics easily. I found that I neglected posting about many of our papers, even though it is important to provide brief and accessible summaries of these papers to enhance their reach. It is important to reach more people, because then we can see whether the paper can stand the test of time and push the state of our u…

Paxos jokes

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For some reason Aleksey finds any joke about Paxos hilarious, whereas Ailidani and I are indifferent to Paxos jokes. However, today out of nowhere I came up with some decent Paxos jokes, and shared them on Twitter.  In the evening I attended the USENIX ATC reception and shared these jokes with Benjamin Reed and Alexander Shraer of ZooKeeper and ZooNet fame, and cracked them up.

Here they are for perpetuity. It is a bad idea to explain jokes. But for pedantic purposes, and to get people interested in Paxos, I provide some explanations. Paxos jokes made simple... err.. moderately complex.

I think the jokes get funnier if you read them in a Russian accent. So give that a try.


Leader - I tell you Paxos joke, if you accept me as leader.
Quorum - Ok comrade.

Leader - Here is joke! (*Transmits joke*)
Quorum - Oookay...

Leader - (*Laughs* hahaha). Now you laugh!!
Quorum - Hahaha, hahaha.


The conversation corresponds to phase 1, phase 2, and phase 3. In Paxos, the leader commits first, and tells the…

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