Talk:Quorum (distributed computing)

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The explanation for quorum based voting is very confusing. Especially the below part :

Every site in the system is assigned a vote Vi. Let us assume that the total number of votes in the system is V and the abort and commit quorums are Va and Vc, respectively. Then the following rules must be obeyed in the implementation of the commit protocol: Va + Vc > V, where 0 < Vc, Va \le V. Before a transaction commits, it must obtain a commit quorum Vc. The total of at least one site that is prepared to commit and zero or more sites waiting \ge Vc.[2] Before a transaction aborts, it must obtain an abort quorum Va The total of zero or more sites that are prepared to abort or any sites waiting \ge Va.


  • What is a quorum?
  • is Va a quorum or the number of abort quorums? It's not clear from the language.
  • What does this sentence even mean ? - The total of zero or more sites that are prepared to abort or any sites waiting \ge Va.

How can anything ever be comitted if Va+Vc>V is required? V is the total number of votes, and each vote can be commit, abort, or unknown. Even if everybody (!) votes for commit, Va (=V) + Vc (0) is not greater than V.